drivers/usb/core/hub.c

   1 /*
   2  * USB hub driver.
   3  *
   4  * (C) Copyright 1999 Linus Torvalds
   5  * (C) Copyright 1999 Johannes Erdfelt
   6  * (C) Copyright 1999 Gregory P. Smith
   7  * (C) Copyright 2001 Brad Hards (bhards@bigpond.net.au)
   8  *
   9  */
  10
  11 #include <linux/config.h>
  12 #include <linux/kernel.h>
  13 #include <linux/errno.h>
  14 #include <linux/module.h>
  15 #include <linux/moduleparam.h>
  16 #include <linux/completion.h>
  17 #include <linux/sched.h>
  18 #include <linux/list.h>
  19 #include <linux/slab.h>
  20 #include <linux/smp_lock.h>
  21 #include <linux/ioctl.h>
  22 #include <linux/usb.h>
  23 #include <linux/usbdevice_fs.h>
  24 #include <linux/kthread.h>
  25 #include <linux/mutex.h>
  26
  27 #include <asm/semaphore.h>
  28 #include <asm/uaccess.h>
  29 #include <asm/byteorder.h>
  30
  31 #include "usb.h"
  32 #include "hcd.h"
  33 #include "hub.h"
  34
  35 /* Protect struct usb_device->state and ->children members
  36  * Note: Both are also protected by ->dev.sem, except that ->state can
  37  * change to USB_STATE_NOTATTACHED even when the semaphore isn't held. */
  38 static DEFINE_SPINLOCK(device_state_lock);
  39
  40 /* khubd's worklist and its lock */
  41 static DEFINE_SPINLOCK(hub_event_lock);
  42 static LIST_HEAD(hub_event_list);       /* List of hubs needing servicing */
  43
  44 /* Wakes up khubd */
  45 static DECLARE_WAIT_QUEUE_HEAD(khubd_wait);
  46
  47 static struct task_struct *khubd_task;
  48
  49 /* cycle leds on hubs that aren't blinking for attention */
  50 static int blinkenlights = 0;
  51 module_param (blinkenlights, bool, S_IRUGO);
  52 MODULE_PARM_DESC (blinkenlights, "true to cycle leds on hubs");
  53
  54 /*
  55  * As of 2.6.10 we introduce a new USB device initialization scheme which
  56  * closely resembles the way Windows works.  Hopefully it will be compatible
  57  * with a wider range of devices than the old scheme.  However some previously
  58  * working devices may start giving rise to "device not accepting address"
  59  * errors; if that happens the user can try the old scheme by adjusting the
  60  * following module parameters.
  61  *
  62  * For maximum flexibility there are two boolean parameters to control the
  63  * hub driver's behavior.  On the first initialization attempt, if the
  64  * "old_scheme_first" parameter is set then the old scheme will be used,
  65  * otherwise the new scheme is used.  If that fails and "use_both_schemes"
  66  * is set, then the driver will make another attempt, using the other scheme.
  67  */
  68 static int old_scheme_first = 0;
  69 module_param(old_scheme_first, bool, S_IRUGO | S_IWUSR);
  70 MODULE_PARM_DESC(old_scheme_first,
  71                  "start with the old device initialization scheme");
  72
  73 static int use_both_schemes = 1;
  74 module_param(use_both_schemes, bool, S_IRUGO | S_IWUSR);
  75 MODULE_PARM_DESC(use_both_schemes,
  76                 "try the other device initialization scheme if the "
  77                 "first one fails");
  78
  79
  80 #ifdef  DEBUG
  81 static inline char *portspeed (int portstatus)
  82 {
  83         if (portstatus & (1 << USB_PORT_FEAT_HIGHSPEED))
  84                 return "480 Mb/s";
  85         else if (portstatus & (1 << USB_PORT_FEAT_LOWSPEED))
  86                 return "1.5 Mb/s";
  87         else
  88                 return "12 Mb/s";
  89 }
  90 #endif
  91
  92 /* Note that hdev or one of its children must be locked! */
  93 static inline struct usb_hub *hdev_to_hub(struct usb_device *hdev)
  94 {
  95         return usb_get_intfdata(hdev->actconfig->interface[0]);
  96 }
  97
  98 /* USB 2.0 spec Section 11.24.4.5 */
  99 static int get_hub_descriptor(struct usb_device *hdev, void *data, int size)
 100 {
 101         int i, ret;
 102
 103         for (i = 0; i < 3; i++) {
 104                 ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 105                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,
 106                         USB_DT_HUB << 8, 0, data, size,
 107                         USB_CTRL_GET_TIMEOUT);
 108                 if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2))
 109                         return ret;
 110         }
 111         return -EINVAL;
 112 }
 113
 114 /*
 115  * USB 2.0 spec Section 11.24.2.1
 116  */
 117 static int clear_hub_feature(struct usb_device *hdev, int feature)
 118 {
 119         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 120                 USB_REQ_CLEAR_FEATURE, USB_RT_HUB, feature, 0, NULL, 0, 1000);
 121 }
 122
 123 /*
 124  * USB 2.0 spec Section 11.24.2.2
 125  */
 126 static int clear_port_feature(struct usb_device *hdev, int port1, int feature)
 127 {
 128         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 129                 USB_REQ_CLEAR_FEATURE, USB_RT_PORT, feature, port1,
 130                 NULL, 0, 1000);
 131 }
 132
 133 /*
 134  * USB 2.0 spec Section 11.24.2.13
 135  */
 136 static int set_port_feature(struct usb_device *hdev, int port1, int feature)
 137 {
 138         return usb_control_msg(hdev, usb_sndctrlpipe(hdev, 0),
 139                 USB_REQ_SET_FEATURE, USB_RT_PORT, feature, port1,
 140                 NULL, 0, 1000);
 141 }
 142
 143 /*
 144  * USB 2.0 spec Section 11.24.2.7.1.10 and table 11-7
 145  * for info about using port indicators
 146  */
 147 static void set_port_led(
 148         struct usb_hub *hub,
 149         int port1,
 150         int selector
 151 )
 152 {
 153         int status = set_port_feature(hub->hdev, (selector << 8) | port1,
 154                         USB_PORT_FEAT_INDICATOR);
 155         if (status < 0)
 156                 dev_dbg (hub->intfdev,
 157                         "port %d indicator %s status %d\n",
 158                         port1,
 159                         ({ char *s; switch (selector) {
 160                         case HUB_LED_AMBER: s = "amber"; break;
 161                         case HUB_LED_GREEN: s = "green"; break;
 162                         case HUB_LED_OFF: s = "off"; break;
 163                         case HUB_LED_AUTO: s = "auto"; break;
 164                         default: s = "??"; break;
 165                         }; s; }),
 166                         status);
 167 }
 168
 169 #define LED_CYCLE_PERIOD        ((2*HZ)/3)
 170
 171 static void led_work (void *__hub)
 172 {
 173         struct usb_hub          *hub = __hub;
 174         struct usb_device       *hdev = hub->hdev;
 175         unsigned                i;
 176         unsigned                changed = 0;
 177         int                     cursor = -1;
 178
 179         if (hdev->state != USB_STATE_CONFIGURED || hub->quiescing)
 180                 return;
 181
 182         for (i = 0; i < hub->descriptor->bNbrPorts; i++) {
 183                 unsigned        selector, mode;
 184
 185                 /* 30%-50% duty cycle */
 186
 187                 switch (hub->indicator[i]) {
 188                 /* cycle marker */
 189                 case INDICATOR_CYCLE:
 190                         cursor = i;
 191                         selector = HUB_LED_AUTO;
 192                         mode = INDICATOR_AUTO;
 193                         break;
 194                 /* blinking green = sw attention */
 195                 case INDICATOR_GREEN_BLINK:
 196                         selector = HUB_LED_GREEN;
 197                         mode = INDICATOR_GREEN_BLINK_OFF;
 198                         break;
 199                 case INDICATOR_GREEN_BLINK_OFF:
 200                         selector = HUB_LED_OFF;
 201                         mode = INDICATOR_GREEN_BLINK;
 202                         break;
 203                 /* blinking amber = hw attention */
 204                 case INDICATOR_AMBER_BLINK:
 205                         selector = HUB_LED_AMBER;
 206                         mode = INDICATOR_AMBER_BLINK_OFF;
 207                         break;
 208                 case INDICATOR_AMBER_BLINK_OFF:
 209                         selector = HUB_LED_OFF;
 210                         mode = INDICATOR_AMBER_BLINK;
 211                         break;
 212                 /* blink green/amber = reserved */
 213                 case INDICATOR_ALT_BLINK:
 214                         selector = HUB_LED_GREEN;
 215                         mode = INDICATOR_ALT_BLINK_OFF;
 216                         break;
 217                 case INDICATOR_ALT_BLINK_OFF:
 218                         selector = HUB_LED_AMBER;
 219                         mode = INDICATOR_ALT_BLINK;
 220                         break;
 221                 default:
 222                         continue;
 223                 }
 224                 if (selector != HUB_LED_AUTO)
 225                         changed = 1;
 226                 set_port_led(hub, i + 1, selector);
 227                 hub->indicator[i] = mode;
 228         }
 229         if (!changed && blinkenlights) {
 230                 cursor++;
 231                 cursor %= hub->descriptor->bNbrPorts;
 232                 set_port_led(hub, cursor + 1, HUB_LED_GREEN);
 233                 hub->indicator[cursor] = INDICATOR_CYCLE;
 234                 changed++;
 235         }
 236         if (changed)
 237                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 238 }
 239
 240 /* use a short timeout for hub/port status fetches */
 241 #define USB_STS_TIMEOUT         1000
 242 #define USB_STS_RETRIES         5
 243
 244 /*
 245  * USB 2.0 spec Section 11.24.2.6
 246  */
 247 static int get_hub_status(struct usb_device *hdev,
 248                 struct usb_hub_status *data)
 249 {
 250         int i, status = -ETIMEDOUT;
 251
 252         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 253                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 254                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_HUB, 0, 0,
 255                         data, sizeof(*data), USB_STS_TIMEOUT);
 256         }
 257         return status;
 258 }
 259
 260 /*
 261  * USB 2.0 spec Section 11.24.2.7
 262  */
 263 static int get_port_status(struct usb_device *hdev, int port1,
 264                 struct usb_port_status *data)
 265 {
 266         int i, status = -ETIMEDOUT;
 267
 268         for (i = 0; i < USB_STS_RETRIES && status == -ETIMEDOUT; i++) {
 269                 status = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 270                         USB_REQ_GET_STATUS, USB_DIR_IN | USB_RT_PORT, 0, port1,
 271                         data, sizeof(*data), USB_STS_TIMEOUT);
 272         }
 273         return status;
 274 }
 275
 276 static void kick_khubd(struct usb_hub *hub)
 277 {
 278         unsigned long   flags;
 279
 280         spin_lock_irqsave(&hub_event_lock, flags);
 281         if (list_empty(&hub->event_list)) {
 282                 list_add_tail(&hub->event_list, &hub_event_list);
 283                 wake_up(&khubd_wait);
 284         }
 285         spin_unlock_irqrestore(&hub_event_lock, flags);
 286 }
 287
 288 void usb_kick_khubd(struct usb_device *hdev)
 289 {
 290         kick_khubd(hdev_to_hub(hdev));
 291 }
 292
 293
 294 /* completion function, fires on port status changes and various faults */
 295 static void hub_irq(struct urb *urb, struct pt_regs *regs)
 296 {
 297         struct usb_hub *hub = (struct usb_hub *)urb->context;
 298         int status;
 299         int i;
 300         unsigned long bits;
 301
 302         switch (urb->status) {
 303         case -ENOENT:           /* synchronous unlink */
 304         case -ECONNRESET:       /* async unlink */
 305         case -ESHUTDOWN:        /* hardware going away */
 306                 return;
 307
 308         default:                /* presumably an error */
 309                 /* Cause a hub reset after 10 consecutive errors */
 310                 dev_dbg (hub->intfdev, "transfer --> %d\n", urb->status);
 311                 if ((++hub->nerrors < 10) || hub->error)
 312                         goto resubmit;
 313                 hub->error = urb->status;
 314                 /* FALL THROUGH */
 315
 316         /* let khubd handle things */
 317         case 0:                 /* we got data:  port status changed */
 318                 bits = 0;
 319                 for (i = 0; i < urb->actual_length; ++i)
 320                         bits |= ((unsigned long) ((*hub->buffer)[i]))
 321                                         << (i*8);
 322                 hub->event_bits[0] = bits;
 323                 break;
 324         }
 325
 326         hub->nerrors = 0;
 327
 328         /* Something happened, let khubd figure it out */
 329         kick_khubd(hub);
 330
 331 resubmit:
 332         if (hub->quiescing)
 333                 return;
 334
 335         if ((status = usb_submit_urb (hub->urb, GFP_ATOMIC)) != 0
 336                         && status != -ENODEV && status != -EPERM)
 337                 dev_err (hub->intfdev, "resubmit --> %d\n", status);
 338 }
 339
 340 /* USB 2.0 spec Section 11.24.2.3 */
 341 static inline int
 342 hub_clear_tt_buffer (struct usb_device *hdev, u16 devinfo, u16 tt)
 343 {
 344         return usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),
 345                                HUB_CLEAR_TT_BUFFER, USB_RT_PORT, devinfo,
 346                                tt, NULL, 0, 1000);
 347 }
 348
 349 /*
 350  * enumeration blocks khubd for a long time. we use keventd instead, since
 351  * long blocking there is the exception, not the rule.  accordingly, HCDs
 352  * talking to TTs must queue control transfers (not just bulk and iso), so
 353  * both can talk to the same hub concurrently.
 354  */
 355 static void hub_tt_kevent (void *arg)
 356 {
 357         struct usb_hub          *hub = arg;
 358         unsigned long           flags;
 359
 360         spin_lock_irqsave (&hub->tt.lock, flags);
 361         while (!list_empty (&hub->tt.clear_list)) {
 362                 struct list_head        *temp;
 363                 struct usb_tt_clear     *clear;
 364                 struct usb_device       *hdev = hub->hdev;
 365                 int                     status;
 366
 367                 temp = hub->tt.clear_list.next;
 368                 clear = list_entry (temp, struct usb_tt_clear, clear_list);
 369                 list_del (&clear->clear_list);
 370
 371                 /* drop lock so HCD can concurrently report other TT errors */
 372                 spin_unlock_irqrestore (&hub->tt.lock, flags);
 373                 status = hub_clear_tt_buffer (hdev, clear->devinfo, clear->tt);
 374                 spin_lock_irqsave (&hub->tt.lock, flags);
 375
 376                 if (status)
 377                         dev_err (&hdev->dev,
 378                                 "clear tt %d (%04x) error %d\n",
 379                                 clear->tt, clear->devinfo, status);
 380                 kfree(clear);
 381         }
 382         spin_unlock_irqrestore (&hub->tt.lock, flags);
 383 }
 384
 385 /**
 386  * usb_hub_tt_clear_buffer - clear control/bulk TT state in high speed hub
 387  * @udev: the device whose split transaction failed
 388  * @pipe: identifies the endpoint of the failed transaction
 389  *
 390  * High speed HCDs use this to tell the hub driver that some split control or
 391  * bulk transaction failed in a way that requires clearing internal state of
 392  * a transaction translator.  This is normally detected (and reported) from
 393  * interrupt context.
 394  *
 395  * It may not be possible for that hub to handle additional full (or low)
 396  * speed transactions until that state is fully cleared out.
 397  */
 398 void usb_hub_tt_clear_buffer (struct usb_device *udev, int pipe)
 399 {
 400         struct usb_tt           *tt = udev->tt;
 401         unsigned long           flags;
 402         struct usb_tt_clear     *clear;
 403
 404         /* we've got to cope with an arbitrary number of pending TT clears,
 405          * since each TT has "at least two" buffers that can need it (and
 406          * there can be many TTs per hub).  even if they're uncommon.
 407          */
 408         if ((clear = kmalloc (sizeof *clear, SLAB_ATOMIC)) == NULL) {
 409                 dev_err (&udev->dev, "can't save CLEAR_TT_BUFFER state\n");
 410                 /* FIXME recover somehow ... RESET_TT? */
 411                 return;
 412         }
 413
 414         /* info that CLEAR_TT_BUFFER needs */
 415         clear->tt = tt->multi ? udev->ttport : 1;
 416         clear->devinfo = usb_pipeendpoint (pipe);
 417         clear->devinfo |= udev->devnum << 4;
 418         clear->devinfo |= usb_pipecontrol (pipe)
 419                         ? (USB_ENDPOINT_XFER_CONTROL << 11)
 420                         : (USB_ENDPOINT_XFER_BULK << 11);
 421         if (usb_pipein (pipe))
 422                 clear->devinfo |= 1 << 15;
 423
 424         /* tell keventd to clear state for this TT */
 425         spin_lock_irqsave (&tt->lock, flags);
 426         list_add_tail (&clear->clear_list, &tt->clear_list);
 427         schedule_work (&tt->kevent);
 428         spin_unlock_irqrestore (&tt->lock, flags);
 429 }
 430
 431 static void hub_power_on(struct usb_hub *hub)
 432 {
 433         int port1;
 434         unsigned pgood_delay = hub->descriptor->bPwrOn2PwrGood * 2;
 435         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 436
 437         /* if hub supports power switching, enable power on each port */
 438         if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2) {
 439                 dev_dbg(hub->intfdev, "enabling power on all ports\n");
 440                 for (port1 = 1; port1 <= hub->descriptor->bNbrPorts; port1++)
 441                         set_port_feature(hub->hdev, port1,
 442                                         USB_PORT_FEAT_POWER);
 443         }
 444
 445         /* Wait at least 100 msec for power to become stable */
 446         msleep(max(pgood_delay, (unsigned) 100));
 447 }
 448
 449 static inline void __hub_quiesce(struct usb_hub *hub)
 450 {
 451         /* (nonblocking) khubd and related activity won't re-trigger */
 452         hub->quiescing = 1;
 453         hub->activating = 0;
 454         hub->resume_root_hub = 0;
 455 }
 456
 457 static void hub_quiesce(struct usb_hub *hub)
 458 {
 459         /* (blocking) stop khubd and related activity */
 460         __hub_quiesce(hub);
 461         usb_kill_urb(hub->urb);
 462         if (hub->has_indicators)
 463                 cancel_delayed_work(&hub->leds);
 464         if (hub->has_indicators || hub->tt.hub)
 465                 flush_scheduled_work();
 466 }
 467
 468 static void hub_activate(struct usb_hub *hub)
 469 {
 470         int     status;
 471
 472         hub->quiescing = 0;
 473         hub->activating = 1;
 474         hub->resume_root_hub = 0;
 475         status = usb_submit_urb(hub->urb, GFP_NOIO);
 476         if (status < 0)
 477                 dev_err(hub->intfdev, "activate --> %d\n", status);
 478         if (hub->has_indicators && blinkenlights)
 479                 schedule_delayed_work(&hub->leds, LED_CYCLE_PERIOD);
 480
 481         /* scan all ports ASAP */
 482         kick_khubd(hub);
 483 }
 484
 485 static int hub_hub_status(struct usb_hub *hub,
 486                 u16 *status, u16 *change)
 487 {
 488         int ret;
 489
 490         ret = get_hub_status(hub->hdev, &hub->status->hub);
 491         if (ret < 0)
 492                 dev_err (hub->intfdev,
 493                         "%s failed (err = %d)\n", __FUNCTION__, ret);
 494         else {
 495                 *status = le16_to_cpu(hub->status->hub.wHubStatus);
 496                 *change = le16_to_cpu(hub->status->hub.wHubChange);
 497                 ret = 0;
 498         }
 499         return ret;
 500 }
 501
 502 static int hub_port_disable(struct usb_hub *hub, int port1, int set_state)
 503 {
 504         struct usb_device *hdev = hub->hdev;
 505         int ret;
 506
 507         if (hdev->children[port1-1] && set_state) {
 508                 usb_set_device_state(hdev->children[port1-1],
 509                                 USB_STATE_NOTATTACHED);
 510         }
 511         ret = clear_port_feature(hdev, port1, USB_PORT_FEAT_ENABLE);
 512         if (ret)
 513                 dev_err(hub->intfdev, "cannot disable port %d (err = %d)\n",
 514                         port1, ret);
 515
 516         return ret;
 517 }
 518
 519
 520 /* caller has locked the hub device */
 521 static void hub_pre_reset(struct usb_hub *hub, int disable_ports)
 522 {
 523         struct usb_device *hdev = hub->hdev;
 524         int port1;
 525
 526         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
 527                 if (hdev->children[port1 - 1]) {
 528                         usb_disconnect(&hdev->children[port1 - 1]);
 529                         if (disable_ports)
 530                                 hub_port_disable(hub, port1, 0);
 531                 }
 532         }
 533         hub_quiesce(hub);
 534 }
 535
 536 /* caller has locked the hub device */
 537 static void hub_post_reset(struct usb_hub *hub)
 538 {
 539         hub_activate(hub);
 540         hub_power_on(hub);
 541 }
 542
 543
 544 static int hub_configure(struct usb_hub *hub,
 545         struct usb_endpoint_descriptor *endpoint)
 546 {
 547         struct usb_device *hdev = hub->hdev;
 548         struct device *hub_dev = hub->intfdev;
 549         u16 hubstatus, hubchange;
 550         u16 wHubCharacteristics;
 551         unsigned int pipe;
 552         int maxp, ret;
 553         char *message;
 554
 555         hub->buffer = usb_buffer_alloc(hdev, sizeof(*hub->buffer), GFP_KERNEL,
 556                         &hub->buffer_dma);
 557         if (!hub->buffer) {
 558                 message = "can't allocate hub irq buffer";
 559                 ret = -ENOMEM;
 560                 goto fail;
 561         }
 562
 563         hub->status = kmalloc(sizeof(*hub->status), GFP_KERNEL);
 564         if (!hub->status) {
 565                 message = "can't kmalloc hub status buffer";
 566                 ret = -ENOMEM;
 567                 goto fail;
 568         }
 569
 570         hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);
 571         if (!hub->descriptor) {
 572                 message = "can't kmalloc hub descriptor";
 573                 ret = -ENOMEM;
 574                 goto fail;
 575         }
 576
 577         /* Request the entire hub descriptor.
 578          * hub->descriptor can handle USB_MAXCHILDREN ports,
 579          * but the hub can/will return fewer bytes here.
 580          */
 581         ret = get_hub_descriptor(hdev, hub->descriptor,
 582                         sizeof(*hub->descriptor));
 583         if (ret < 0) {
 584                 message = "can't read hub descriptor";
 585                 goto fail;
 586         } else if (hub->descriptor->bNbrPorts > USB_MAXCHILDREN) {
 587                 message = "hub has too many ports!";
 588                 ret = -ENODEV;
 589                 goto fail;
 590         }
 591
 592         hdev->maxchild = hub->descriptor->bNbrPorts;
 593         dev_info (hub_dev, "%d port%s detected\n", hdev->maxchild,
 594                 (hdev->maxchild == 1) ? "" : "s");
 595
 596         wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
 597
 598         if (wHubCharacteristics & HUB_CHAR_COMPOUND) {
 599                 int     i;
 600                 char    portstr [USB_MAXCHILDREN + 1];
 601
 602                 for (i = 0; i < hdev->maxchild; i++)
 603                         portstr[i] = hub->descriptor->DeviceRemovable
 604                                     [((i + 1) / 8)] & (1 << ((i + 1) % 8))
 605                                 ? 'F' : 'R';
 606                 portstr[hdev->maxchild] = 0;
 607                 dev_dbg(hub_dev, "compound device; port removable status: %s\n", portstr);
 608         } else
 609                 dev_dbg(hub_dev, "standalone hub\n");
 610
 611         switch (wHubCharacteristics & HUB_CHAR_LPSM) {
 612                 case 0x00:
 613                         dev_dbg(hub_dev, "ganged power switching\n");
 614                         break;
 615                 case 0x01:
 616                         dev_dbg(hub_dev, "individual port power switching\n");
 617                         break;
 618                 case 0x02:
 619                 case 0x03:
 620                         dev_dbg(hub_dev, "no power switching (usb 1.0)\n");
 621                         break;
 622         }
 623
 624         switch (wHubCharacteristics & HUB_CHAR_OCPM) {
 625                 case 0x00:
 626                         dev_dbg(hub_dev, "global over-current protection\n");
 627                         break;
 628                 case 0x08:
 629                         dev_dbg(hub_dev, "individual port over-current protection\n");
 630                         break;
 631                 case 0x10:
 632                 case 0x18:
 633                         dev_dbg(hub_dev, "no over-current protection\n");
 634                         break;
 635         }
 636
 637         spin_lock_init (&hub->tt.lock);
 638         INIT_LIST_HEAD (&hub->tt.clear_list);
 639         INIT_WORK (&hub->tt.kevent, hub_tt_kevent, hub);
 640         switch (hdev->descriptor.bDeviceProtocol) {
 641                 case 0:
 642                         break;
 643                 case 1:
 644                         dev_dbg(hub_dev, "Single TT\n");
 645                         hub->tt.hub = hdev;
 646                         break;
 647                 case 2:
 648                         ret = usb_set_interface(hdev, 0, 1);
 649                         if (ret == 0) {
 650                                 dev_dbg(hub_dev, "TT per port\n");
 651                                 hub->tt.multi = 1;
 652                         } else
 653                                 dev_err(hub_dev, "Using single TT (err %d)\n",
 654                                         ret);
 655                         hub->tt.hub = hdev;
 656                         break;
 657                 default:
 658                         dev_dbg(hub_dev, "Unrecognized hub protocol %d\n",
 659                                 hdev->descriptor.bDeviceProtocol);
 660                         break;
 661         }
 662
 663         /* Note 8 FS bit times == (8 bits / 12000000 bps) ~= 666ns */
 664         switch (wHubCharacteristics & HUB_CHAR_TTTT) {
 665                 case HUB_TTTT_8_BITS:
 666                         if (hdev->descriptor.bDeviceProtocol != 0) {
 667                                 hub->tt.think_time = 666;
 668                                 dev_dbg(hub_dev, "TT requires at most %d "
 669                                                 "FS bit times (%d ns)\n",
 670                                         8, hub->tt.think_time);
 671                         }
 672                         break;
 673                 case HUB_TTTT_16_BITS:
 674                         hub->tt.think_time = 666 * 2;
 675                         dev_dbg(hub_dev, "TT requires at most %d "
 676                                         "FS bit times (%d ns)\n",
 677                                 16, hub->tt.think_time);
 678                         break;
 679                 case HUB_TTTT_24_BITS:
 680                         hub->tt.think_time = 666 * 3;
 681                         dev_dbg(hub_dev, "TT requires at most %d "
 682                                         "FS bit times (%d ns)\n",
 683                                 24, hub->tt.think_time);
 684                         break;
 685                 case HUB_TTTT_32_BITS:
 686                         hub->tt.think_time = 666 * 4;
 687                         dev_dbg(hub_dev, "TT requires at most %d "
 688                                         "FS bit times (%d ns)\n",
 689                                 32, hub->tt.think_time);
 690                         break;
 691         }
 692
 693         /* probe() zeroes hub->indicator[] */
 694         if (wHubCharacteristics & HUB_CHAR_PORTIND) {
 695                 hub->has_indicators = 1;
 696                 dev_dbg(hub_dev, "Port indicators are supported\n");
 697         }
 698
 699         dev_dbg(hub_dev, "power on to power good time: %dms\n",
 700                 hub->descriptor->bPwrOn2PwrGood * 2);
 701
 702         /* power budgeting mostly matters with bus-powered hubs,
 703          * and battery-powered root hubs (may provide just 8 mA).
 704          */
 705         ret = usb_get_status(hdev, USB_RECIP_DEVICE, 0, &hubstatus);
 706         if (ret < 2) {
 707                 message = "can't get hub status";
 708                 goto fail;
 709         }
 710         le16_to_cpus(&hubstatus);
 711         if (hdev == hdev->bus->root_hub) {
 712                 if (hdev->bus_mA == 0 || hdev->bus_mA >= 500)
 713                         hub->mA_per_port = 500;
 714                 else {
 715                         hub->mA_per_port = hdev->bus_mA;
 716                         hub->limited_power = 1;
 717                 }
 718         } else if ((hubstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
 719                 dev_dbg(hub_dev, "hub controller current requirement: %dmA\n",
 720                         hub->descriptor->bHubContrCurrent);
 721                 hub->limited_power = 1;
 722                 if (hdev->maxchild > 0) {
 723                         int remaining = hdev->bus_mA -
 724                                         hub->descriptor->bHubContrCurrent;
 725
 726                         if (remaining < hdev->maxchild * 100)
 727                                 dev_warn(hub_dev,
 728                                         "insufficient power available "
 729                                         "to use all downstream ports\n");
 730                         hub->mA_per_port = 100;         /* 7.2.1.1 */
 731                 }
 732         } else {        /* Self-powered external hub */
 733                 /* FIXME: What about battery-powered external hubs that
 734                  * provide less current per port? */
 735                 hub->mA_per_port = 500;
 736         }
 737         if (hub->mA_per_port < 500)
 738                 dev_dbg(hub_dev, "%umA bus power budget for each child\n",
 739                                 hub->mA_per_port);
 740
 741         ret = hub_hub_status(hub, &hubstatus, &hubchange);
 742         if (ret < 0) {
 743                 message = "can't get hub status";
 744                 goto fail;
 745         }
 746
 747         /* local power status reports aren't always correct */
 748         if (hdev->actconfig->desc.bmAttributes & USB_CONFIG_ATT_SELFPOWER)
 749                 dev_dbg(hub_dev, "local power source is %s\n",
 750                         (hubstatus & HUB_STATUS_LOCAL_POWER)
 751                         ? "lost (inactive)" : "good");
 752
 753         if ((wHubCharacteristics & HUB_CHAR_OCPM) == 0)
 754                 dev_dbg(hub_dev, "%sover-current condition exists\n",
 755                         (hubstatus & HUB_STATUS_OVERCURRENT) ? "" : "no ");
 756
 757         /* set up the interrupt endpoint */
 758         pipe = usb_rcvintpipe(hdev, endpoint->bEndpointAddress);
 759         maxp = usb_maxpacket(hdev, pipe, usb_pipeout(pipe));
 760
 761         if (maxp > sizeof(*hub->buffer))
 762                 maxp = sizeof(*hub->buffer);
 763
 764         hub->urb = usb_alloc_urb(0, GFP_KERNEL);
 765         if (!hub->urb) {
 766                 message = "couldn't allocate interrupt urb";
 767                 ret = -ENOMEM;
 768                 goto fail;
 769         }
 770
 771         usb_fill_int_urb(hub->urb, hdev, pipe, *hub->buffer, maxp, hub_irq,
 772                 hub, endpoint->bInterval);
 773         hub->urb->transfer_dma = hub->buffer_dma;
 774         hub->urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
 775
 776         /* maybe cycle the hub leds */
 777         if (hub->has_indicators && blinkenlights)
 778                 hub->indicator [0] = INDICATOR_CYCLE;
 779
 780         hub_power_on(hub);
 781         hub_activate(hub);
 782         return 0;
 783
 784 fail:
 785         dev_err (hub_dev, "config failed, %s (err %d)\n",
 786                         message, ret);
 787         /* hub_disconnect() frees urb and descriptor */
 788         return ret;
 789 }
 790
 791 static unsigned highspeed_hubs;
 792
 793 static void hub_disconnect(struct usb_interface *intf)
 794 {
 795         struct usb_hub *hub = usb_get_intfdata (intf);
 796         struct usb_device *hdev;
 797
 798         usb_set_intfdata (intf, NULL);
 799         hdev = hub->hdev;
 800
 801         if (hdev->speed == USB_SPEED_HIGH)
 802                 highspeed_hubs--;
 803
 804         /* Disconnect all children and quiesce the hub */
 805         hub_pre_reset(hub, 1);
 806
 807         usb_free_urb(hub->urb);
 808         hub->urb = NULL;
 809
 810         spin_lock_irq(&hub_event_lock);
 811         list_del_init(&hub->event_list);
 812         spin_unlock_irq(&hub_event_lock);
 813
 814         kfree(hub->descriptor);
 815         hub->descriptor = NULL;
 816
 817         kfree(hub->status);
 818         hub->status = NULL;
 819
 820         if (hub->buffer) {
 821                 usb_buffer_free(hdev, sizeof(*hub->buffer), hub->buffer,
 822                                 hub->buffer_dma);
 823                 hub->buffer = NULL;
 824         }
 825
 826         kfree(hub);
 827 }
 828
 829 static int hub_probe(struct usb_interface *intf, const struct usb_device_id *id)
 830 {
 831         struct usb_host_interface *desc;
 832         struct usb_endpoint_descriptor *endpoint;
 833         struct usb_device *hdev;
 834         struct usb_hub *hub;
 835
 836         desc = intf->cur_altsetting;
 837         hdev = interface_to_usbdev(intf);
 838
 839         /* Some hubs have a subclass of 1, which AFAICT according to the */
 840         /*  specs is not defined, but it works */
 841         if ((desc->desc.bInterfaceSubClass != 0) &&
 842             (desc->desc.bInterfaceSubClass != 1)) {
 843 descriptor_error:
 844                 dev_err (&intf->dev, "bad descriptor, ignoring hub\n");
 845                 return -EIO;
 846         }
 847
 848         /* Multiple endpoints? What kind of mutant ninja-hub is this? */
 849         if (desc->desc.bNumEndpoints != 1)
 850                 goto descriptor_error;
 851
 852         endpoint = &desc->endpoint[0].desc;
 853
 854         /* Output endpoint? Curiouser and curiouser.. */
 855         if (!(endpoint->bEndpointAddress & USB_DIR_IN))
 856                 goto descriptor_error;
 857
 858         /* If it's not an interrupt endpoint, we'd better punt! */
 859         if ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
 860                         != USB_ENDPOINT_XFER_INT)
 861                 goto descriptor_error;
 862
 863         /* We found a hub */
 864         dev_info (&intf->dev, "USB hub found\n");
 865
 866         hub = kzalloc(sizeof(*hub), GFP_KERNEL);
 867         if (!hub) {
 868                 dev_dbg (&intf->dev, "couldn't kmalloc hub struct\n");
 869                 return -ENOMEM;
 870         }
 871
 872         INIT_LIST_HEAD(&hub->event_list);
 873         hub->intfdev = &intf->dev;
 874         hub->hdev = hdev;
 875         INIT_WORK(&hub->leds, led_work, hub);
 876
 877         usb_set_intfdata (intf, hub);
 878
 879         if (hdev->speed == USB_SPEED_HIGH)
 880                 highspeed_hubs++;
 881
 882         if (hub_configure(hub, endpoint) >= 0)
 883                 return 0;
 884
 885         hub_disconnect (intf);
 886         return -ENODEV;
 887 }
 888
 889 static int
 890 hub_ioctl(struct usb_interface *intf, unsigned int code, void *user_data)
 891 {
 892         struct usb_device *hdev = interface_to_usbdev (intf);
 893
 894         /* assert ifno == 0 (part of hub spec) */
 895         switch (code) {
 896         case USBDEVFS_HUB_PORTINFO: {
 897                 struct usbdevfs_hub_portinfo *info = user_data;
 898                 int i;
 899
 900                 spin_lock_irq(&device_state_lock);
 901                 if (hdev->devnum <= 0)
 902                         info->nports = 0;
 903                 else {
 904                         info->nports = hdev->maxchild;
 905                         for (i = 0; i < info->nports; i++) {
 906                                 if (hdev->children[i] == NULL)
 907                                         info->port[i] = 0;
 908                                 else
 909                                         info->port[i] =
 910                                                 hdev->children[i]->devnum;
 911                         }
 912                 }
 913                 spin_unlock_irq(&device_state_lock);
 914
 915                 return info->nports + 1;
 916                 }
 917
 918         default:
 919                 return -ENOSYS;
 920         }
 921 }
 922
 923
 924 /* grab device/port lock, returning index of that port (zero based).
 925  * protects the upstream link used by this device from concurrent
 926  * tree operations like suspend, resume, reset, and disconnect, which
 927  * apply to everything downstream of a given port.
 928  */
 929 static int locktree(struct usb_device *udev)
 930 {
 931         int                     t;
 932         struct usb_device       *hdev;
 933
 934         if (!udev)
 935                 return -ENODEV;
 936
 937         /* root hub is always the first lock in the series */
 938         hdev = udev->parent;
 939         if (!hdev) {
 940                 usb_lock_device(udev);
 941                 return 0;
 942         }
 943
 944         /* on the path from root to us, lock everything from
 945          * top down, dropping parent locks when not needed
 946          */
 947         t = locktree(hdev);
 948         if (t < 0)
 949                 return t;
 950
 951         /* everything is fail-fast once disconnect
 952          * processing starts
 953          */
 954         if (udev->state == USB_STATE_NOTATTACHED) {
 955                 usb_unlock_device(hdev);
 956                 return -ENODEV;
 957         }
 958
 959         /* when everyone grabs locks top->bottom,
 960          * non-overlapping work may be concurrent
 961          */
 962         usb_lock_device(udev);
 963         usb_unlock_device(hdev);
 964         return udev->portnum;
 965 }
 966
 967 static void recursively_mark_NOTATTACHED(struct usb_device *udev)
 968 {
 969         int i;
 970
 971         for (i = 0; i < udev->maxchild; ++i) {
 972                 if (udev->children[i])
 973                         recursively_mark_NOTATTACHED(udev->children[i]);
 974         }
 975         udev->state = USB_STATE_NOTATTACHED;
 976 }
 977
 978 /**
 979  * usb_set_device_state - change a device's current state (usbcore, hcds)
 980  * @udev: pointer to device whose state should be changed
 981  * @new_state: new state value to be stored
 982  *
 983  * udev->state is _not_ fully protected by the device lock.  Although
 984  * most transitions are made only while holding the lock, the state can
 985  * can change to USB_STATE_NOTATTACHED at almost any time.  This
 986  * is so that devices can be marked as disconnected as soon as possible,
 987  * without having to wait for any semaphores to be released.  As a result,
 988  * all changes to any device's state must be protected by the
 989  * device_state_lock spinlock.
 990  *
 991  * Once a device has been added to the device tree, all changes to its state
 992  * should be made using this routine.  The state should _not_ be set directly.
 993  *
 994  * If udev->state is already USB_STATE_NOTATTACHED then no change is made.
 995  * Otherwise udev->state is set to new_state, and if new_state is
 996  * USB_STATE_NOTATTACHED then all of udev's descendants' states are also set
 997  * to USB_STATE_NOTATTACHED.
 998  */
 999 void usb_set_device_state(struct usb_device *udev,
1000                 enum usb_device_state new_state)
1001 {
1002         unsigned long flags;
1003
1004         spin_lock_irqsave(&device_state_lock, flags);
1005         if (udev->state == USB_STATE_NOTATTACHED)
1006                 ;       /* do nothing */
1007         else if (new_state != USB_STATE_NOTATTACHED) {
1008                 udev->state = new_state;
1009                 if (new_state == USB_STATE_CONFIGURED)
1010                         device_init_wakeup(&udev->dev,
1011                                 (udev->actconfig->desc.bmAttributes
1012                                  & USB_CONFIG_ATT_WAKEUP));
1013                 else if (new_state != USB_STATE_SUSPENDED)
1014                         device_init_wakeup(&udev->dev, 0);
1015         } else
1016                 recursively_mark_NOTATTACHED(udev);
1017         spin_unlock_irqrestore(&device_state_lock, flags);
1018 }
1019 EXPORT_SYMBOL(usb_set_device_state);
1020
1021
1022 #ifdef CONFIG_PM
1023
1024 /**
1025  * usb_root_hub_lost_power - called by HCD if the root hub lost Vbus power
1026  * @rhdev: struct usb_device for the root hub
1027  *
1028  * The USB host controller driver calls this function when its root hub
1029  * is resumed and Vbus power has been interrupted or the controller
1030  * has been reset.  The routine marks all the children of the root hub
1031  * as NOTATTACHED and marks logical connect-change events on their ports.
1032  */
1033 void usb_root_hub_lost_power(struct usb_device *rhdev)
1034 {
1035         struct usb_hub *hub;
1036         int port1;
1037         unsigned long flags;
1038
1039         dev_warn(&rhdev->dev, "root hub lost power or was reset\n");
1040         spin_lock_irqsave(&device_state_lock, flags);
1041         hub = hdev_to_hub(rhdev);
1042         for (port1 = 1; port1 <= rhdev->maxchild; ++port1) {
1043                 if (rhdev->children[port1 - 1]) {
1044                         recursively_mark_NOTATTACHED(
1045                                         rhdev->children[port1 - 1]);
1046                         set_bit(port1, hub->change_bits);
1047                 }
1048         }
1049         spin_unlock_irqrestore(&device_state_lock, flags);
1050 }
1051 EXPORT_SYMBOL_GPL(usb_root_hub_lost_power);
1052
1053 #endif
1054
1055 static void choose_address(struct usb_device *udev)
1056 {
1057         int             devnum;
1058         struct usb_bus  *bus = udev->bus;
1059
1060         /* If khubd ever becomes multithreaded, this will need a lock */
1061
1062         /* Try to allocate the next devnum beginning at bus->devnum_next. */
1063         devnum = find_next_zero_bit(bus->devmap.devicemap, 128,
1064                         bus->devnum_next);
1065         if (devnum >= 128)
1066                 devnum = find_next_zero_bit(bus->devmap.devicemap, 128, 1);
1067
1068         bus->devnum_next = ( devnum >= 127 ? 1 : devnum + 1);
1069
1070         if (devnum < 128) {
1071                 set_bit(devnum, bus->devmap.devicemap);
1072                 udev->devnum = devnum;
1073         }
1074 }
1075
1076 static void release_address(struct usb_device *udev)
1077 {
1078         if (udev->devnum > 0) {
1079                 clear_bit(udev->devnum, udev->bus->devmap.devicemap);
1080                 udev->devnum = -1;
1081         }
1082 }
1083
1084 /**
1085  * usb_disconnect - disconnect a device (usbcore-internal)
1086  * @pdev: pointer to device being disconnected
1087  * Context: !in_interrupt ()
1088  *
1089  * Something got disconnected. Get rid of it and all of its children.
1090  *
1091  * If *pdev is a normal device then the parent hub must already be locked.
1092  * If *pdev is a root hub then this routine will acquire the
1093  * usb_bus_list_lock on behalf of the caller.
1094  *
1095  * Only hub drivers (including virtual root hub drivers for host
1096  * controllers) should ever call this.
1097  *
1098  * This call is synchronous, and may not be used in an interrupt context.
1099  */
1100 void usb_disconnect(struct usb_device **pdev)
1101 {
1102         struct usb_device       *udev = *pdev;
1103         int                     i;
1104
1105         if (!udev) {
1106                 pr_debug ("%s nodev\n", __FUNCTION__);
1107                 return;
1108         }
1109
1110         /* mark the device as inactive, so any further urb submissions for
1111          * this device (and any of its children) will fail immediately.
1112          * this quiesces everyting except pending urbs.
1113          */
1114         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1115         dev_info (&udev->dev, "USB disconnect, address %d\n", udev->devnum);
1116
1117         usb_lock_device(udev);
1118
1119         /* Free up all the children before we remove this device */
1120         for (i = 0; i < USB_MAXCHILDREN; i++) {
1121                 if (udev->children[i])
1122                         usb_disconnect(&udev->children[i]);
1123         }
1124
1125         /* deallocate hcd/hardware state ... nuking all pending urbs and
1126          * cleaning up all state associated with the current configuration
1127          * so that the hardware is now fully quiesced.
1128          */
1129         usb_disable_device(udev, 0);
1130
1131         usb_notify_remove_device(udev);
1132
1133         /* Free the device number, remove the /proc/bus/usb entry and
1134          * the sysfs attributes, and delete the parent's children[]
1135          * (or root_hub) pointer.
1136          */
1137         dev_dbg (&udev->dev, "unregistering device\n");
1138         release_address(udev);
1139         usb_remove_sysfs_dev_files(udev);
1140
1141         /* Avoid races with recursively_mark_NOTATTACHED() */
1142         spin_lock_irq(&device_state_lock);
1143         *pdev = NULL;
1144         spin_unlock_irq(&device_state_lock);
1145
1146         usb_unlock_device(udev);
1147
1148         device_unregister(&udev->dev);
1149 }
1150
1151 static inline const char *plural(int n)
1152 {
1153         return (n == 1 ? "" : "s");
1154 }
1155
1156 static int choose_configuration(struct usb_device *udev)
1157 {
1158         int i;
1159         u16 devstatus;
1160         int bus_powered;
1161         int num_configs;
1162         struct usb_host_config *c, *best;
1163
1164         /* If this fails, assume the device is bus-powered */
1165         devstatus = 0;
1166         usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1167         le16_to_cpus(&devstatus);
1168         bus_powered = ((devstatus & (1 << USB_DEVICE_SELF_POWERED)) == 0);
1169         dev_dbg(&udev->dev, "device is %s-powered\n",
1170                         bus_powered ? "bus" : "self");
1171
1172         best = NULL;
1173         c = udev->config;
1174         num_configs = udev->descriptor.bNumConfigurations;
1175         for (i = 0; i < num_configs; (i++, c++)) {
1176                 struct usb_interface_descriptor *desc =
1177                                 &c->intf_cache[0]->altsetting->desc;
1178
1179                 /*
1180                  * HP's USB bus-powered keyboard has only one configuration
1181                  * and it claims to be self-powered; other devices may have
1182                  * similar errors in their descriptors.  If the next test
1183                  * were allowed to execute, such configurations would always
1184                  * be rejected and the devices would not work as expected.
1185                  */
1186 #if 0
1187                 /* Rule out self-powered configs for a bus-powered device */
1188                 if (bus_powered && (c->desc.bmAttributes &
1189                                         USB_CONFIG_ATT_SELFPOWER))
1190                         continue;
1191 #endif
1192
1193                 /*
1194                  * The next test may not be as effective as it should be.
1195                  * Some hubs have errors in their descriptor, claiming
1196                  * to be self-powered when they are really bus-powered.
1197                  * We will overestimate the amount of current such hubs
1198                  * make available for each port.
1199                  *
1200                  * This is a fairly benign sort of failure.  It won't
1201                  * cause us to reject configurations that we should have
1202                  * accepted.
1203                  */
1204
1205                 /* Rule out configs that draw too much bus current */
1206                 if (c->desc.bMaxPower * 2 > udev->bus_mA)
1207                         continue;
1208
1209                 /* If the first config's first interface is COMM/2/0xff
1210                  * (MSFT RNDIS), rule it out unless Linux has host-side
1211                  * RNDIS support. */
1212                 if (i == 0 && desc->bInterfaceClass == USB_CLASS_COMM
1213                                 && desc->bInterfaceSubClass == 2
1214                                 && desc->bInterfaceProtocol == 0xff) {
1215 #ifndef CONFIG_USB_NET_RNDIS
1216                         continue;
1217 #else
1218                         best = c;
1219 #endif
1220                 }
1221
1222                 /* From the remaining configs, choose the first one whose
1223                  * first interface is for a non-vendor-specific class.
1224                  * Reason: Linux is more likely to have a class driver
1225                  * than a vendor-specific driver. */
1226                 else if (udev->descriptor.bDeviceClass !=
1227                                                 USB_CLASS_VENDOR_SPEC &&
1228                                 desc->bInterfaceClass !=
1229                                                 USB_CLASS_VENDOR_SPEC) {
1230                         best = c;
1231                         break;
1232                 }
1233
1234                 /* If all the remaining configs are vendor-specific,
1235                  * choose the first one. */
1236                 else if (!best)
1237                         best = c;
1238         }
1239
1240         if (best) {
1241                 i = best->desc.bConfigurationValue;
1242                 dev_info(&udev->dev,
1243                         "configuration #%d chosen from %d choice%s\n",
1244                         i, num_configs, plural(num_configs));
1245         } else {
1246                 i = -1;
1247                 dev_warn(&udev->dev,
1248                         "no configuration chosen from %d choice%s\n",
1249                         num_configs, plural(num_configs));
1250         }
1251         return i;
1252 }
1253
1254 #ifdef DEBUG
1255 static void show_string(struct usb_device *udev, char *id, char *string)
1256 {
1257         if (!string)
1258                 return;
1259         dev_printk(KERN_INFO, &udev->dev, "%s: %s\n", id, string);
1260 }
1261
1262 #else
1263 static inline void show_string(struct usb_device *udev, char *id, char *string)
1264 {}
1265 #endif
1266
1267
1268 #ifdef  CONFIG_USB_OTG
1269 #include "otg_whitelist.h"
1270 #endif
1271
1272 /**
1273  * usb_new_device - perform initial device setup (usbcore-internal)
1274  * @udev: newly addressed device (in ADDRESS state)
1275  *
1276  * This is called with devices which have been enumerated, but not yet
1277  * configured.  The device descriptor is available, but not descriptors
1278  * for any device configuration.  The caller must have locked either
1279  * the parent hub (if udev is a normal device) or else the
1280  * usb_bus_list_lock (if udev is a root hub).  The parent's pointer to
1281  * udev has already been installed, but udev is not yet visible through
1282  * sysfs or other filesystem code.
1283  *
1284  * Returns 0 for success (device is configured and listed, with its
1285  * interfaces, in sysfs); else a negative errno value.
1286  *
1287  * This call is synchronous, and may not be used in an interrupt context.
1288  *
1289  * Only the hub driver or root-hub registrar should ever call this.
1290  */
1291 int usb_new_device(struct usb_device *udev)
1292 {
1293         int err;
1294         int c;
1295
1296         err = usb_get_configuration(udev);
1297         if (err < 0) {
1298                 dev_err(&udev->dev, "can't read configurations, error %d\n",
1299                         err);
1300                 goto fail;
1301         }
1302
1303         /* read the standard strings and cache them if present */
1304         udev->product = usb_cache_string(udev, udev->descriptor.iProduct);
1305         udev->manufacturer = usb_cache_string(udev,
1306                         udev->descriptor.iManufacturer);
1307         udev->serial = usb_cache_string(udev, udev->descriptor.iSerialNumber);
1308
1309         /* Tell the world! */
1310         dev_dbg(&udev->dev, "new device strings: Mfr=%d, Product=%d, "
1311                         "SerialNumber=%d\n",
1312                         udev->descriptor.iManufacturer,
1313                         udev->descriptor.iProduct,
1314                         udev->descriptor.iSerialNumber);
1315         show_string(udev, "Product", udev->product);
1316         show_string(udev, "Manufacturer", udev->manufacturer);
1317         show_string(udev, "SerialNumber", udev->serial);
1318
1319 #ifdef  CONFIG_USB_OTG
1320         /*
1321          * OTG-aware devices on OTG-capable root hubs may be able to use SRP,
1322          * to wake us after we've powered off VBUS; and HNP, switching roles
1323          * "host" to "peripheral".  The OTG descriptor helps figure this out.
1324          */
1325         if (!udev->bus->is_b_host
1326                         && udev->config
1327                         && udev->parent == udev->bus->root_hub) {
1328                 struct usb_otg_descriptor       *desc = 0;
1329                 struct usb_bus                  *bus = udev->bus;
1330
1331                 /* descriptor may appear anywhere in config */
1332                 if (__usb_get_extra_descriptor (udev->rawdescriptors[0],
1333                                         le16_to_cpu(udev->config[0].desc.wTotalLength),
1334                                         USB_DT_OTG, (void **) &desc) == 0) {
1335                         if (desc->bmAttributes & USB_OTG_HNP) {
1336                                 unsigned                port1 = udev->portnum;
1337                                 struct usb_device       *root = udev->parent;
1338
1339                                 dev_info(&udev->dev,
1340                                         "Dual-Role OTG device on %sHNP port\n",
1341                                         (port1 == bus->otg_port)
1342                                                 ? "" : "non-");
1343
1344                                 /* enable HNP before suspend, it's simpler */
1345                                 if (port1 == bus->otg_port)
1346                                         bus->b_hnp_enable = 1;
1347                                 err = usb_control_msg(udev,
1348                                         usb_sndctrlpipe(udev, 0),
1349                                         USB_REQ_SET_FEATURE, 0,
1350                                         bus->b_hnp_enable
1351                                                 ? USB_DEVICE_B_HNP_ENABLE
1352                                                 : USB_DEVICE_A_ALT_HNP_SUPPORT,
1353                                         0, NULL, 0, USB_CTRL_SET_TIMEOUT);
1354                                 if (err < 0) {
1355                                         /* OTG MESSAGE: report errors here,
1356                                          * customize to match your product.
1357                                          */
1358                                         dev_info(&udev->dev,
1359                                                 "can't set HNP mode; %d\n",
1360                                                 err);
1361                                         bus->b_hnp_enable = 0;
1362                                 }
1363                         }
1364                 }
1365         }
1366
1367         if (!is_targeted(udev)) {
1368
1369                 /* Maybe it can talk to us, though we can't talk to it.
1370                  * (Includes HNP test device.)
1371                  */
1372                 if (udev->bus->b_hnp_enable || udev->bus->is_b_host) {
1373                         static int __usb_suspend_device(struct usb_device *,
1374                                                 int port1);
1375                         err = __usb_suspend_device(udev, udev->bus->otg_port);
1376                         if (err < 0)
1377                                 dev_dbg(&udev->dev, "HNP fail, %d\n", err);
1378                 }
1379                 err = -ENODEV;
1380                 goto fail;
1381         }
1382 #endif
1383
1384         /* put device-specific files into sysfs */
1385         err = device_add (&udev->dev);
1386         if (err) {
1387                 dev_err(&udev->dev, "can't device_add, error %d\n", err);
1388                 goto fail;
1389         }
1390         usb_create_sysfs_dev_files (udev);
1391
1392         usb_lock_device(udev);
1393
1394         /* choose and set the configuration. that registers the interfaces
1395          * with the driver core, and lets usb device drivers bind to them.
1396          */
1397         c = choose_configuration(udev);
1398         if (c >= 0) {
1399                 err = usb_set_configuration(udev, c);
1400                 if (err) {
1401                         dev_err(&udev->dev, "can't set config #%d, error %d\n",
1402                                         c, err);
1403                         /* This need not be fatal.  The user can try to
1404                          * set other configurations. */
1405                 }
1406         }
1407
1408         /* USB device state == configured ... usable */
1409         usb_notify_add_device(udev);
1410
1411         usb_unlock_device(udev);
1412
1413         return 0;
1414
1415 fail:
1416         usb_set_device_state(udev, USB_STATE_NOTATTACHED);
1417         return err;
1418 }
1419
1420
1421 static int hub_port_status(struct usb_hub *hub, int port1,
1422                                u16 *status, u16 *change)
1423 {
1424         int ret;
1425
1426         ret = get_port_status(hub->hdev, port1, &hub->status->port);
1427         if (ret < 0)
1428                 dev_err (hub->intfdev,
1429                         "%s failed (err = %d)\n", __FUNCTION__, ret);
1430         else {
1431                 *status = le16_to_cpu(hub->status->port.wPortStatus);
1432                 *change = le16_to_cpu(hub->status->port.wPortChange);
1433                 ret = 0;
1434         }
1435         return ret;
1436 }
1437
1438 #define PORT_RESET_TRIES        5
1439 #define SET_ADDRESS_TRIES       2
1440 #define GET_DESCRIPTOR_TRIES    2
1441 #define SET_CONFIG_TRIES        (2 * (use_both_schemes + 1))
1442 #define USE_NEW_SCHEME(i)       ((i) / 2 == old_scheme_first)
1443
1444 #define HUB_ROOT_RESET_TIME     50      /* times are in msec */
1445 #define HUB_SHORT_RESET_TIME    10
1446 #define HUB_LONG_RESET_TIME     200
1447 #define HUB_RESET_TIMEOUT       500
1448
1449 static int hub_port_wait_reset(struct usb_hub *hub, int port1,
1450                                 struct usb_device *udev, unsigned int delay)
1451 {
1452         int delay_time, ret;
1453         u16 portstatus;
1454         u16 portchange;
1455
1456         for (delay_time = 0;
1457                         delay_time < HUB_RESET_TIMEOUT;
1458                         delay_time += delay) {
1459                 /* wait to give the device a chance to reset */
1460                 msleep(delay);
1461
1462                 /* read and decode port status */
1463                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
1464                 if (ret < 0)
1465                         return ret;
1466
1467                 /* Device went away? */
1468                 if (!(portstatus & USB_PORT_STAT_CONNECTION))
1469                         return -ENOTCONN;
1470
1471                 /* bomb out completely if something weird happened */
1472                 if ((portchange & USB_PORT_STAT_C_CONNECTION))
1473                         return -EINVAL;
1474
1475                 /* if we`ve finished resetting, then break out of the loop */
1476                 if (!(portstatus & USB_PORT_STAT_RESET) &&
1477                     (portstatus & USB_PORT_STAT_ENABLE)) {
1478                         if (portstatus & USB_PORT_STAT_HIGH_SPEED)
1479                                 udev->speed = USB_SPEED_HIGH;
1480                         else if (portstatus & USB_PORT_STAT_LOW_SPEED)
1481                                 udev->speed = USB_SPEED_LOW;
1482                         else
1483                                 udev->speed = USB_SPEED_FULL;
1484                         return 0;
1485                 }
1486
1487                 /* switch to the long delay after two short delay failures */
1488                 if (delay_time >= 2 * HUB_SHORT_RESET_TIME)
1489                         delay = HUB_LONG_RESET_TIME;
1490
1491                 dev_dbg (hub->intfdev,
1492                         "port %d not reset yet, waiting %dms\n",
1493                         port1, delay);
1494         }
1495
1496         return -EBUSY;
1497 }
1498
1499 static int hub_port_reset(struct usb_hub *hub, int port1,
1500                                 struct usb_device *udev, unsigned int delay)
1501 {
1502         int i, status;
1503
1504         /* Reset the port */
1505         for (i = 0; i < PORT_RESET_TRIES; i++) {
1506                 status = set_port_feature(hub->hdev,
1507                                 port1, USB_PORT_FEAT_RESET);
1508                 if (status)
1509                         dev_err(hub->intfdev,
1510                                         "cannot reset port %d (err = %d)\n",
1511                                         port1, status);
1512                 else {
1513                         status = hub_port_wait_reset(hub, port1, udev, delay);
1514                         if (status && status != -ENOTCONN)
1515                                 dev_dbg(hub->intfdev,
1516                                                 "port_wait_reset: err = %d\n",
1517                                                 status);
1518                 }
1519
1520                 /* return on disconnect or reset */
1521                 switch (status) {
1522                 case 0:
1523                         /* TRSTRCY = 10 ms; plus some extra */
1524                         msleep(10 + 40);
1525                         /* FALL THROUGH */
1526                 case -ENOTCONN:
1527                 case -ENODEV:
1528                         clear_port_feature(hub->hdev,
1529                                 port1, USB_PORT_FEAT_C_RESET);
1530                         /* FIXME need disconnect() for NOTATTACHED device */
1531                         usb_set_device_state(udev, status
1532                                         ? USB_STATE_NOTATTACHED
1533                                         : USB_STATE_DEFAULT);
1534                         return status;
1535                 }
1536
1537                 dev_dbg (hub->intfdev,
1538                         "port %d not enabled, trying reset again...\n",
1539                         port1);
1540                 delay = HUB_LONG_RESET_TIME;
1541         }
1542
1543         dev_err (hub->intfdev,
1544                 "Cannot enable port %i.  Maybe the USB cable is bad?\n",
1545                 port1);
1546
1547         return status;
1548 }
1549
1550 /*
1551  * Disable a port and mark a logical connnect-change event, so that some
1552  * time later khubd will disconnect() any existing usb_device on the port
1553  * and will re-enumerate if there actually is a device attached.
1554  */
1555 static void hub_port_logical_disconnect(struct usb_hub *hub, int port1)
1556 {
1557         dev_dbg(hub->intfdev, "logical disconnect on port %d\n", port1);
1558         hub_port_disable(hub, port1, 1);
1559
1560         /* FIXME let caller ask to power down the port:
1561          *  - some devices won't enumerate without a VBUS power cycle
1562          *  - SRP saves power that way
1563          *  - ... new call, TBD ...
1564          * That's easy if this hub can switch power per-port, and
1565          * khubd reactivates the port later (timer, SRP, etc).
1566          * Powerdown must be optional, because of reset/DFU.
1567          */
1568
1569         set_bit(port1, hub->change_bits);
1570         kick_khubd(hub);
1571 }
1572
1573
1574 #ifdef  CONFIG_USB_SUSPEND
1575
1576 /*
1577  * Selective port suspend reduces power; most suspended devices draw
1578  * less than 500 uA.  It's also used in OTG, along with remote wakeup.
1579  * All devices below the suspended port are also suspended.
1580  *
1581  * Devices leave suspend state when the host wakes them up.  Some devices
1582  * also support "remote wakeup", where the device can activate the USB
1583  * tree above them to deliver data, such as a keypress or packet.  In
1584  * some cases, this wakes the USB host.
1585  */
1586 static int hub_port_suspend(struct usb_hub *hub, int port1,
1587                 struct usb_device *udev)
1588 {
1589         int     status;
1590
1591         // dev_dbg(hub->intfdev, "suspend port %d\n", port1);
1592
1593         /* enable remote wakeup when appropriate; this lets the device
1594          * wake up the upstream hub (including maybe the root hub).
1595          *
1596          * NOTE:  OTG devices may issue remote wakeup (or SRP) even when
1597          * we don't explicitly enable it here.
1598          */
1599         if (device_may_wakeup(&udev->dev)) {
1600                 status = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1601                                 USB_REQ_SET_FEATURE, USB_RECIP_DEVICE,
1602                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1603                                 NULL, 0,
1604                                 USB_CTRL_SET_TIMEOUT);
1605                 if (status)
1606                         dev_dbg(&udev->dev,
1607                                 "won't remote wakeup, status %d\n",
1608                                 status);
1609         }
1610
1611         /* see 7.1.7.6 */
1612         status = set_port_feature(hub->hdev, port1, USB_PORT_FEAT_SUSPEND);
1613         if (status) {
1614                 dev_dbg(hub->intfdev,
1615                         "can't suspend port %d, status %d\n",
1616                         port1, status);
1617                 /* paranoia:  "should not happen" */
1618                 (void) usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
1619                                 USB_REQ_CLEAR_FEATURE, USB_RECIP_DEVICE,
1620                                 USB_DEVICE_REMOTE_WAKEUP, 0,
1621                                 NULL, 0,
1622                                 USB_CTRL_SET_TIMEOUT);
1623         } else {
1624                 /* device has up to 10 msec to fully suspend */
1625                 dev_dbg(&udev->dev, "usb suspend\n");
1626                 usb_set_device_state(udev, USB_STATE_SUSPENDED);
1627                 msleep(10);
1628         }
1629         return status;
1630 }
1631
1632 /*
1633  * Devices on USB hub ports have only one "suspend" state, corresponding
1634  * to ACPI D2, "may cause the device to lose some context".
1635  * State transitions include:
1636  *
1637  *   - suspend, resume ... when the VBUS power link stays live
1638  *   - suspend, disconnect ... VBUS lost
1639  *
1640  * Once VBUS drop breaks the circuit, the port it's using has to go through
1641  * normal re-enumeration procedures, starting with enabling VBUS power.
1642  * Other than re-initializing the hub (plug/unplug, except for root hubs),
1643  * Linux (2.6) currently has NO mechanisms to initiate that:  no khubd
1644  * timer, no SRP, no requests through sysfs.
1645  *
1646  * If CONFIG_USB_SUSPEND isn't enabled, devices only really suspend when
1647  * the root hub for their bus goes into global suspend ... so we don't
1648  * (falsely) update the device power state to say it suspended.
1649  */
1650 static int __usb_suspend_device (struct usb_device *udev, int port1)
1651 {
1652         int     status = 0;
1653
1654         /* caller owns the udev device lock */
1655         if (port1 < 0)
1656                 return port1;
1657
1658         if (udev->state == USB_STATE_SUSPENDED
1659                         || udev->state == USB_STATE_NOTATTACHED) {
1660                 return 0;
1661         }
1662
1663         /* all interfaces must already be suspended */
1664         if (udev->actconfig) {
1665                 int     i;
1666
1667                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1668                         struct usb_interface    *intf;
1669
1670                         intf = udev->actconfig->interface[i];
1671                         if (is_active(intf)) {
1672                                 dev_dbg(&intf->dev, "nyet suspended\n");
1673                                 return -EBUSY;
1674                         }
1675                 }
1676         }
1677
1678         /* we only change a device's upstream USB link.
1679          * root hubs have no upstream USB link.
1680          */
1681         if (udev->parent)
1682                 status = hub_port_suspend(hdev_to_hub(udev->parent), port1,
1683                                 udev);
1684
1685         if (status == 0)
1686                 udev->dev.power.power_state = PMSG_SUSPEND;
1687         return status;
1688 }
1689
1690 #endif
1691
1692 /*
1693  * usb_suspend_device - suspend a usb device
1694  * @udev: device that's no longer in active use
1695  * Context: must be able to sleep; device not locked; pm locks held
1696  *
1697  * Suspends a USB device that isn't in active use, conserving power.
1698  * Devices may wake out of a suspend, if anything important happens,
1699  * using the remote wakeup mechanism.  They may also be taken out of
1700  * suspend by the host, using usb_resume_device().  It's also routine
1701  * to disconnect devices while they are suspended.
1702  *
1703  * This only affects the USB hardware for a device; its interfaces
1704  * (and, for hubs, child devices) must already have been suspended.
1705  *
1706  * Suspending OTG devices may trigger HNP, if that's been enabled
1707  * between a pair of dual-role devices.  That will change roles, such
1708  * as from A-Host to A-Peripheral or from B-Host back to B-Peripheral.
1709  *
1710  * Returns 0 on success, else negative errno.
1711  */
1712 int usb_suspend_device(struct usb_device *udev)
1713 {
1714 #ifdef  CONFIG_USB_SUSPEND
1715         if (udev->state == USB_STATE_NOTATTACHED)
1716                 return -ENODEV;
1717         return __usb_suspend_device(udev, udev->portnum);
1718 #else
1719         /* NOTE:  udev->state unchanged, it's not lying ... */
1720         udev->dev.power.power_state = PMSG_SUSPEND;
1721         return 0;
1722 #endif
1723 }
1724
1725 /*
1726  * If the USB "suspend" state is in use (rather than "global suspend"),
1727  * many devices will be individually taken out of suspend state using
1728  * special" resume" signaling.  These routines kick in shortly after
1729  * hardware resume signaling is finished, either because of selective
1730  * resume (by host) or remote wakeup (by device) ... now see what changed
1731  * in the tree that's rooted at this device.
1732  */
1733 static int finish_device_resume(struct usb_device *udev)
1734 {
1735         int     status;
1736         u16     devstatus;
1737
1738         /* caller owns the udev device lock */
1739         dev_dbg(&udev->dev, "finish resume\n");
1740
1741         /* usb ch9 identifies four variants of SUSPENDED, based on what
1742          * state the device resumes to.  Linux currently won't see the
1743          * first two on the host side; they'd be inside hub_port_init()
1744          * during many timeouts, but khubd can't suspend until later.
1745          */
1746         usb_set_device_state(udev, udev->actconfig
1747                         ? USB_STATE_CONFIGURED
1748                         : USB_STATE_ADDRESS);
1749         udev->dev.power.power_state = PMSG_ON;
1750
1751         /* 10.5.4.5 says be sure devices in the tree are still there.
1752          * For now let's assume the device didn't go crazy on resume,
1753          * and device drivers will know about any resume quirks.
1754          */
1755         status = usb_get_status(udev, USB_RECIP_DEVICE, 0, &devstatus);
1756         if (status < 2)
1757                 dev_dbg(&udev->dev,
1758                         "gone after usb resume? status %d\n",
1759                         status);
1760         else if (udev->actconfig) {
1761                 unsigned        i;
1762                 int             (*resume)(struct device *);
1763
1764                 le16_to_cpus(&devstatus);
1765                 if ((devstatus & (1 << USB_DEVICE_REMOTE_WAKEUP))
1766                                 && udev->parent) {
1767                         status = usb_control_msg(udev,
1768                                         usb_sndctrlpipe(udev, 0),
1769                                         USB_REQ_CLEAR_FEATURE,
1770                                                 USB_RECIP_DEVICE,
1771                                         USB_DEVICE_REMOTE_WAKEUP, 0,
1772                                         NULL, 0,
1773                                         USB_CTRL_SET_TIMEOUT);
1774                         if (status) {
1775                                 dev_dbg(&udev->dev, "disable remote "
1776                                         "wakeup, status %d\n", status);
1777                                 status = 0;
1778                         }
1779                 }
1780
1781                 /* resume interface drivers; if this is a hub, it
1782                  * may have a child resume event to deal with soon
1783                  */
1784                 resume = udev->dev.bus->resume;
1785                 for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
1786                         struct device *dev =
1787                                         &udev->actconfig->interface[i]->dev;
1788
1789                         down(&dev->sem);
1790                         (void) resume(dev);
1791                         up(&dev->sem);
1792                 }
1793                 status = 0;
1794
1795         } else if (udev->devnum <= 0) {
1796                 dev_dbg(&udev->dev, "bogus resume!\n");
1797                 status = -EINVAL;
1798         }
1799         return status;
1800 }
1801
1802 #ifdef  CONFIG_USB_SUSPEND
1803
1804 static int
1805 hub_port_resume(struct usb_hub *hub, int port1, struct usb_device *udev)
1806 {
1807         int     status;
1808
1809         // dev_dbg(hub->intfdev, "resume port %d\n", port1);
1810
1811         /* see 7.1.7.7; affects power usage, but not budgeting */
1812         status = clear_port_feature(hub->hdev,
1813                         port1, USB_PORT_FEAT_SUSPEND);
1814         if (status) {
1815                 dev_dbg(hub->intfdev,
1816                         "can't resume port %d, status %d\n",
1817                         port1, status);
1818         } else {
1819                 u16             devstatus;
1820                 u16             portchange;
1821
1822                 /* drive resume for at least 20 msec */
1823                 if (udev)
1824                         dev_dbg(&udev->dev, "RESUME\n");
1825                 msleep(25);
1826
1827 #define LIVE_FLAGS      ( USB_PORT_STAT_POWER \
1828                         | USB_PORT_STAT_ENABLE \
1829                         | USB_PORT_STAT_CONNECTION)
1830
1831                 /* Virtual root hubs can trigger on GET_PORT_STATUS to
1832                  * stop resume signaling.  Then finish the resume
1833                  * sequence.
1834                  */
1835                 devstatus = portchange = 0;
1836                 status = hub_port_status(hub, port1,
1837                                 &devstatus, &portchange);
1838                 if (status < 0
1839                                 || (devstatus & LIVE_FLAGS) != LIVE_FLAGS
1840                                 || (devstatus & USB_PORT_STAT_SUSPEND) != 0
1841                                 ) {
1842                         dev_dbg(hub->intfdev,
1843                                 "port %d status %04x.%04x after resume, %d\n",
1844                                 port1, portchange, devstatus, status);
1845                 } else {
1846                         /* TRSMRCY = 10 msec */
1847                         msleep(10);
1848                         if (udev)
1849                                 status = finish_device_resume(udev);
1850                 }
1851         }
1852         if (status < 0)
1853                 hub_port_logical_disconnect(hub, port1);
1854
1855         return status;
1856 }
1857
1858 #endif
1859
1860 /*
1861  * usb_resume_device - re-activate a suspended usb device
1862  * @udev: device to re-activate
1863  * Context: must be able to sleep; device not locked; pm locks held
1864  *
1865  * This will re-activate the suspended device, increasing power usage
1866  * while letting drivers communicate again with its endpoints.
1867  * USB resume explicitly guarantees that the power session between
1868  * the host and the device is the same as it was when the device
1869  * suspended.
1870  *
1871  * Returns 0 on success, else negative errno.
1872  */
1873 int usb_resume_device(struct usb_device *udev)
1874 {
1875         int     status;
1876
1877         if (udev->state == USB_STATE_NOTATTACHED)
1878                 return -ENODEV;
1879
1880 #ifdef  CONFIG_USB_SUSPEND
1881         /* selective resume of one downstream hub-to-device port */
1882         if (udev->parent) {
1883                 if (udev->state == USB_STATE_SUSPENDED) {
1884                         // NOTE swsusp may bork us, device state being wrong...
1885                         // NOTE this fails if parent is also suspended...
1886                         status = hub_port_resume(hdev_to_hub(udev->parent),
1887                                         udev->portnum, udev);
1888                 } else
1889                         status = 0;
1890         } else
1891 #endif
1892                 status = finish_device_resume(udev);
1893         if (status < 0)
1894                 dev_dbg(&udev->dev, "can't resume, status %d\n",
1895                         status);
1896
1897         /* rebind drivers that had no suspend() */
1898         if (status == 0) {
1899                 usb_unlock_device(udev);
1900                 bus_rescan_devices(&usb_bus_type);
1901                 usb_lock_device(udev);
1902         }
1903         return status;
1904 }
1905
1906 static int remote_wakeup(struct usb_device *udev)
1907 {
1908         int     status = 0;
1909
1910 #ifdef  CONFIG_USB_SUSPEND
1911
1912         /* don't repeat RESUME sequence if this device
1913          * was already woken up by some other task
1914          */
1915         usb_lock_device(udev);
1916         if (udev->state == USB_STATE_SUSPENDED) {
1917                 dev_dbg(&udev->dev, "RESUME (wakeup)\n");
1918                 /* TRSMRCY = 10 msec */
1919                 msleep(10);
1920                 status = finish_device_resume(udev);
1921         }
1922         usb_unlock_device(udev);
1923 #endif
1924         return status;
1925 }
1926
1927 static int hub_suspend(struct usb_interface *intf, pm_message_t msg)
1928 {
1929         struct usb_hub          *hub = usb_get_intfdata (intf);
1930         struct usb_device       *hdev = hub->hdev;
1931         unsigned                port1;
1932
1933         /* fail if children aren't already suspended */
1934         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
1935                 struct usb_device       *udev;
1936
1937                 udev = hdev->children [port1-1];
1938                 if (udev && (udev->dev.power.power_state.event
1939                                         == PM_EVENT_ON
1940 #ifdef  CONFIG_USB_SUSPEND
1941                                 || udev->state != USB_STATE_SUSPENDED
1942 #endif
1943                                 )) {
1944                         dev_dbg(&intf->dev, "port %d nyet suspended\n", port1);
1945                         return -EBUSY;
1946                 }
1947         }
1948
1949         /* "global suspend" of the downstream HC-to-USB interface */
1950         if (!hdev->parent) {
1951                 struct usb_bus  *bus = hdev->bus;
1952                 if (bus) {
1953                         int     status = hcd_bus_suspend (bus);
1954
1955                         if (status != 0) {
1956                                 dev_dbg(&hdev->dev, "'global' suspend %d\n",
1957                                         status);
1958                                 return status;
1959                         }
1960                 } else
1961                         return -EOPNOTSUPP;
1962         }
1963
1964         /* stop khubd and related activity */
1965         hub_quiesce(hub);
1966         return 0;
1967 }
1968
1969 static int hub_resume(struct usb_interface *intf)
1970 {
1971         struct usb_device       *hdev = interface_to_usbdev(intf);
1972         struct usb_hub          *hub = usb_get_intfdata (intf);
1973         int                     status;
1974
1975         /* "global resume" of the downstream HC-to-USB interface */
1976         if (!hdev->parent) {
1977                 struct usb_bus  *bus = hdev->bus;
1978                 if (bus) {
1979                         status = hcd_bus_resume (bus);
1980                         if (status) {
1981                                 dev_dbg(&intf->dev, "'global' resume %d\n",
1982                                         status);
1983                                 return status;
1984                         }
1985                 } else
1986                         return -EOPNOTSUPP;
1987                 if (status == 0) {
1988                         /* TRSMRCY = 10 msec */
1989                         msleep(10);
1990                 }
1991         }
1992
1993         hub_activate(hub);
1994
1995         /* REVISIT:  this recursion probably shouldn't exist.  Remove
1996          * this code sometime, after retesting with different root and
1997          * external hubs.
1998          */
1999 #ifdef  CONFIG_USB_SUSPEND
2000         {
2001         unsigned                port1;
2002
2003         for (port1 = 1; port1 <= hdev->maxchild; port1++) {
2004                 struct usb_device       *udev;
2005                 u16                     portstat, portchange;
2006
2007                 udev = hdev->children [port1-1];
2008                 status = hub_port_status(hub, port1, &portstat, &portchange);
2009                 if (status == 0) {
2010                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2011                                 clear_port_feature(hdev, port1,
2012                                         USB_PORT_FEAT_C_SUSPEND);
2013                                 portchange &= ~USB_PORT_STAT_C_SUSPEND;
2014                         }
2015
2016                         /* let khubd handle disconnects etc */
2017                         if (portchange)
2018                                 continue;
2019                 }
2020
2021                 if (!udev || status < 0)
2022                         continue;
2023                 usb_lock_device(udev);
2024                 if (portstat & USB_PORT_STAT_SUSPEND)
2025                         status = hub_port_resume(hub, port1, udev);
2026                 else {
2027                         status = finish_device_resume(udev);
2028                         if (status < 0) {
2029                                 dev_dbg(&intf->dev, "resume port %d --> %d\n",
2030                                         port1, status);
2031                                 hub_port_logical_disconnect(hub, port1);
2032                         }
2033                 }
2034                 usb_unlock_device(udev);
2035         }
2036         }
2037 #endif
2038         return 0;
2039 }
2040
2041 void usb_suspend_root_hub(struct usb_device *hdev)
2042 {
2043         struct usb_hub *hub = hdev_to_hub(hdev);
2044
2045         /* This also makes any led blinker stop retriggering.  We're called
2046          * from irq, so the blinker might still be scheduled.  Caller promises
2047          * that the root hub status URB will be canceled.
2048          */
2049         __hub_quiesce(hub);
2050         mark_quiesced(to_usb_interface(hub->intfdev));
2051 }
2052
2053 void usb_resume_root_hub(struct usb_device *hdev)
2054 {
2055         struct usb_hub *hub = hdev_to_hub(hdev);
2056
2057         hub->resume_root_hub = 1;
2058         kick_khubd(hub);
2059 }
2060
2061
2062 /* USB 2.0 spec, 7.1.7.3 / fig 7-29:
2063  *
2064  * Between connect detection and reset signaling there must be a delay
2065  * of 100ms at least for debounce and power-settling.  The corresponding
2066  * timer shall restart whenever the downstream port detects a disconnect.
2067  *
2068  * Apparently there are some bluetooth and irda-dongles and a number of
2069  * low-speed devices for which this debounce period may last over a second.
2070  * Not covered by the spec - but easy to deal with.
2071  *
2072  * This implementation uses a 1500ms total debounce timeout; if the
2073  * connection isn't stable by then it returns -ETIMEDOUT.  It checks
2074  * every 25ms for transient disconnects.  When the port status has been
2075  * unchanged for 100ms it returns the port status.
2076  */
2077
2078 #define HUB_DEBOUNCE_TIMEOUT    1500
2079 #define HUB_DEBOUNCE_STEP         25
2080 #define HUB_DEBOUNCE_STABLE      100
2081
2082 static int hub_port_debounce(struct usb_hub *hub, int port1)
2083 {
2084         int ret;
2085         int total_time, stable_time = 0;
2086         u16 portchange, portstatus;
2087         unsigned connection = 0xffff;
2088
2089         for (total_time = 0; ; total_time += HUB_DEBOUNCE_STEP) {
2090                 ret = hub_port_status(hub, port1, &portstatus, &portchange);
2091                 if (ret < 0)
2092                         return ret;
2093
2094                 if (!(portchange & USB_PORT_STAT_C_CONNECTION) &&
2095                      (portstatus & USB_PORT_STAT_CONNECTION) == connection) {
2096                         stable_time += HUB_DEBOUNCE_STEP;
2097                         if (stable_time >= HUB_DEBOUNCE_STABLE)
2098                                 break;
2099                 } else {
2100                         stable_time = 0;
2101                         connection = portstatus & USB_PORT_STAT_CONNECTION;
2102                 }
2103
2104                 if (portchange & USB_PORT_STAT_C_CONNECTION) {
2105                         clear_port_feature(hub->hdev, port1,
2106                                         USB_PORT_FEAT_C_CONNECTION);
2107                 }
2108
2109                 if (total_time >= HUB_DEBOUNCE_TIMEOUT)
2110                         break;
2111                 msleep(HUB_DEBOUNCE_STEP);
2112         }
2113
2114         dev_dbg (hub->intfdev,
2115                 "debounce: port %d: total %dms stable %dms status 0x%x\n",
2116                 port1, total_time, stable_time, portstatus);
2117
2118         if (stable_time < HUB_DEBOUNCE_STABLE)
2119                 return -ETIMEDOUT;
2120         return portstatus;
2121 }
2122
2123 static void ep0_reinit(struct usb_device *udev)
2124 {
2125         usb_disable_endpoint(udev, 0 + USB_DIR_IN);
2126         usb_disable_endpoint(udev, 0 + USB_DIR_OUT);
2127         udev->ep_in[0] = udev->ep_out[0] = &udev->ep0;
2128 }
2129
2130 #define usb_sndaddr0pipe()      (PIPE_CONTROL << 30)
2131 #define usb_rcvaddr0pipe()      ((PIPE_CONTROL << 30) | USB_DIR_IN)
2132
2133 static int hub_set_address(struct usb_device *udev)
2134 {
2135         int retval;
2136
2137         if (udev->devnum == 0)
2138                 return -EINVAL;
2139         if (udev->state == USB_STATE_ADDRESS)
2140                 return 0;
2141         if (udev->state != USB_STATE_DEFAULT)
2142                 return -EINVAL;
2143         retval = usb_control_msg(udev, usb_sndaddr0pipe(),
2144                 USB_REQ_SET_ADDRESS, 0, udev->devnum, 0,
2145                 NULL, 0, USB_CTRL_SET_TIMEOUT);
2146         if (retval == 0) {
2147                 usb_set_device_state(udev, USB_STATE_ADDRESS);
2148                 ep0_reinit(udev);
2149         }
2150         return retval;
2151 }
2152
2153 /* Reset device, (re)assign address, get device descriptor.
2154  * Device connection must be stable, no more debouncing needed.
2155  * Returns device in USB_STATE_ADDRESS, except on error.
2156  *
2157  * If this is called for an already-existing device (as part of
2158  * usb_reset_device), the caller must own the device lock.  For a
2159  * newly detected device that is not accessible through any global
2160  * pointers, it's not necessary to lock the device.
2161  */
2162 static int
2163 hub_port_init (struct usb_hub *hub, struct usb_device *udev, int port1,
2164                 int retry_counter)
2165 {
2166         static DEFINE_MUTEX(usb_address0_mutex);
2167
2168         struct usb_device       *hdev = hub->hdev;
2169         int                     i, j, retval;
2170         unsigned                delay = HUB_SHORT_RESET_TIME;
2171         enum usb_device_speed   oldspeed = udev->speed;
2172
2173         /* root hub ports have a slightly longer reset period
2174          * (from USB 2.0 spec, section 7.1.7.5)
2175          */
2176         if (!hdev->parent) {
2177                 delay = HUB_ROOT_RESET_TIME;
2178                 if (port1 == hdev->bus->otg_port)
2179                         hdev->bus->b_hnp_enable = 0;
2180         }
2181
2182         /* Some low speed devices have problems with the quick delay, so */
2183         /*  be a bit pessimistic with those devices. RHbug #23670 */
2184         if (oldspeed == USB_SPEED_LOW)
2185                 delay = HUB_LONG_RESET_TIME;
2186
2187         mutex_lock(&usb_address0_mutex);
2188
2189         /* Reset the device; full speed may morph to high speed */
2190         retval = hub_port_reset(hub, port1, udev, delay);
2191         if (retval < 0)         /* error or disconnect */
2192                 goto fail;
2193                                 /* success, speed is known */
2194         retval = -ENODEV;
2195
2196         if (oldspeed != USB_SPEED_UNKNOWN && oldspeed != udev->speed) {
2197                 dev_dbg(&udev->dev, "device reset changed speed!\n");
2198                 goto fail;
2199         }
2200         oldspeed = udev->speed;
2201
2202         /* USB 2.0 section 5.5.3 talks about ep0 maxpacket ...
2203          * it's fixed size except for full speed devices.
2204          */
2205         switch (udev->speed) {
2206         case USB_SPEED_HIGH:            /* fixed at 64 */
2207                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2208                 break;
2209         case USB_SPEED_FULL:            /* 8, 16, 32, or 64 */
2210                 /* to determine the ep0 maxpacket size, try to read
2211                  * the device descriptor to get bMaxPacketSize0 and
2212                  * then correct our initial guess.
2213                  */
2214                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(64);
2215                 break;
2216         case USB_SPEED_LOW:             /* fixed at 8 */
2217                 udev->ep0.desc.wMaxPacketSize = __constant_cpu_to_le16(8);
2218                 break;
2219         default:
2220                 goto fail;
2221         }
2222
2223         dev_info (&udev->dev,
2224                         "%s %s speed USB device using %s and address %d\n",
2225                         (udev->config) ? "reset" : "new",
2226                         ({ char *speed; switch (udev->speed) {
2227                         case USB_SPEED_LOW:     speed = "low";  break;
2228                         case USB_SPEED_FULL:    speed = "full"; break;
2229                         case USB_SPEED_HIGH:    speed = "high"; break;
2230                         default:                speed = "?";    break;
2231                         }; speed;}),
2232                         udev->bus->controller->driver->name,
2233                         udev->devnum);
2234
2235         /* Set up TT records, if needed  */
2236         if (hdev->tt) {
2237                 udev->tt = hdev->tt;
2238                 udev->ttport = hdev->ttport;
2239         } else if (udev->speed != USB_SPEED_HIGH
2240                         && hdev->speed == USB_SPEED_HIGH) {
2241                 udev->tt = &hub->tt;
2242                 udev->ttport = port1;
2243         }
2244
2245         /* Why interleave GET_DESCRIPTOR and SET_ADDRESS this way?
2246          * Because device hardware and firmware is sometimes buggy in
2247          * this area, and this is how Linux has done it for ages.
2248          * Change it cautiously.
2249          *
2250          * NOTE:  If USE_NEW_SCHEME() is true we will start by issuing
2251          * a 64-byte GET_DESCRIPTOR request.  This is what Windows does,
2252          * so it may help with some non-standards-compliant devices.
2253          * Otherwise we start with SET_ADDRESS and then try to read the
2254          * first 8 bytes of the device descriptor to get the ep0 maxpacket
2255          * value.
2256          */
2257         for (i = 0; i < GET_DESCRIPTOR_TRIES; (++i, msleep(100))) {
2258                 if (USE_NEW_SCHEME(retry_counter)) {
2259                         struct usb_device_descriptor *buf;
2260                         int r = 0;
2261
2262 #define GET_DESCRIPTOR_BUFSIZE  64
2263                         buf = kmalloc(GET_DESCRIPTOR_BUFSIZE, GFP_NOIO);
2264                         if (!buf) {
2265                                 retval = -ENOMEM;
2266                                 continue;
2267                         }
2268
2269                         /* Use a short timeout the first time through,
2270                          * so that recalcitrant full-speed devices with
2271                          * 8- or 16-byte ep0-maxpackets won't slow things
2272                          * down tremendously by NAKing the unexpectedly
2273                          * early status stage.  Also, retry on all errors;
2274                          * some devices are flakey.
2275                          */
2276                         for (j = 0; j < 3; ++j) {
2277                                 buf->bMaxPacketSize0 = 0;
2278                                 r = usb_control_msg(udev, usb_rcvaddr0pipe(),
2279                                         USB_REQ_GET_DESCRIPTOR, USB_DIR_IN,
2280                                         USB_DT_DEVICE << 8, 0,
2281                                         buf, GET_DESCRIPTOR_BUFSIZE,
2282                                         (i ? USB_CTRL_GET_TIMEOUT : 1000));
2283                                 switch (buf->bMaxPacketSize0) {
2284                                 case 8: case 16: case 32: case 64:
2285                                         if (buf->bDescriptorType ==
2286                                                         USB_DT_DEVICE) {
2287                                                 r = 0;
2288                                                 break;
2289                                         }
2290                                         /* FALL THROUGH */
2291                                 default:
2292                                         if (r == 0)
2293                                                 r = -EPROTO;
2294                                         break;
2295                                 }
2296                                 if (r == 0)
2297                                         break;
2298                         }
2299                         udev->descriptor.bMaxPacketSize0 =
2300                                         buf->bMaxPacketSize0;
2301                         kfree(buf);
2302
2303                         retval = hub_port_reset(hub, port1, udev, delay);
2304                         if (retval < 0)         /* error or disconnect */
2305                                 goto fail;
2306                         if (oldspeed != udev->speed) {
2307                                 dev_dbg(&udev->dev,
2308                                         "device reset changed speed!\n");
2309                                 retval = -ENODEV;
2310                                 goto fail;
2311                         }
2312                         if (r) {
2313                                 dev_err(&udev->dev, "device descriptor "
2314                                                 "read/%s, error %d\n",
2315                                                 "64", r);
2316                                 retval = -EMSGSIZE;
2317                                 continue;
2318                         }
2319 #undef GET_DESCRIPTOR_BUFSIZE
2320                 }
2321
2322                 for (j = 0; j < SET_ADDRESS_TRIES; ++j) {
2323                         retval = hub_set_address(udev);
2324                         if (retval >= 0)
2325                                 break;
2326                         msleep(200);
2327                 }
2328                 if (retval < 0) {
2329                         dev_err(&udev->dev,
2330                                 "device not accepting address %d, error %d\n",
2331                                 udev->devnum, retval);
2332                         goto fail;
2333                 }
2334
2335                 /* cope with hardware quirkiness:
2336                  *  - let SET_ADDRESS settle, some device hardware wants it
2337                  *  - read ep0 maxpacket even for high and low speed,
2338                  */
2339                 msleep(10);
2340                 if (USE_NEW_SCHEME(retry_counter))
2341                         break;
2342
2343                 retval = usb_get_device_descriptor(udev, 8);
2344                 if (retval < 8) {
2345                         dev_err(&udev->dev, "device descriptor "
2346                                         "read/%s, error %d\n",
2347                                         "8", retval);
2348                         if (retval >= 0)
2349                                 retval = -EMSGSIZE;
2350                 } else {
2351                         retval = 0;
2352                         break;
2353                 }
2354         }
2355         if (retval)
2356                 goto fail;
2357
2358         i = udev->descriptor.bMaxPacketSize0;
2359         if (le16_to_cpu(udev->ep0.desc.wMaxPacketSize) != i) {
2360                 if (udev->speed != USB_SPEED_FULL ||
2361                                 !(i == 8 || i == 16 || i == 32 || i == 64)) {
2362                         dev_err(&udev->dev, "ep0 maxpacket = %d\n", i);
2363                         retval = -EMSGSIZE;
2364                         goto fail;
2365                 }
2366                 dev_dbg(&udev->dev, "ep0 maxpacket = %d\n", i);
2367                 udev->ep0.desc.wMaxPacketSize = cpu_to_le16(i);
2368                 ep0_reinit(udev);
2369         }
2370
2371         retval = usb_get_device_descriptor(udev, USB_DT_DEVICE_SIZE);
2372         if (retval < (signed)sizeof(udev->descriptor)) {
2373                 dev_err(&udev->dev, "device descriptor read/%s, error %d\n",
2374                         "all", retval);
2375                 if (retval >= 0)
2376                         retval = -ENOMSG;
2377                 goto fail;
2378         }
2379
2380         retval = 0;
2381
2382 fail:
2383         if (retval)
2384                 hub_port_disable(hub, port1, 0);
2385         mutex_unlock(&usb_address0_mutex);
2386         return retval;
2387 }
2388
2389 static void
2390 check_highspeed (struct usb_hub *hub, struct usb_device *udev, int port1)
2391 {
2392         struct usb_qualifier_descriptor *qual;
2393         int                             status;
2394
2395         qual = kmalloc (sizeof *qual, SLAB_KERNEL);
2396         if (qual == NULL)
2397                 return;
2398
2399         status = usb_get_descriptor (udev, USB_DT_DEVICE_QUALIFIER, 0,
2400                         qual, sizeof *qual);
2401         if (status == sizeof *qual) {
2402                 dev_info(&udev->dev, "not running at top speed; "
2403                         "connect to a high speed hub\n");
2404                 /* hub LEDs are probably harder to miss than syslog */
2405                 if (hub->has_indicators) {
2406                         hub->indicator[port1-1] = INDICATOR_GREEN_BLINK;
2407                         schedule_work (&hub->leds);
2408                 }
2409         }
2410         kfree(qual);
2411 }
2412
2413 static unsigned
2414 hub_power_remaining (struct usb_hub *hub)
2415 {
2416         struct usb_device *hdev = hub->hdev;
2417         int remaining;
2418         int port1;
2419
2420         if (!hub->limited_power)
2421                 return 0;
2422
2423         remaining = hdev->bus_mA - hub->descriptor->bHubContrCurrent;
2424         for (port1 = 1; port1 <= hdev->maxchild; ++port1) {
2425                 struct usb_device       *udev = hdev->children[port1 - 1];
2426                 int                     delta;
2427
2428                 if (!udev)
2429                         continue;
2430
2431                 /* Unconfigured devices may not use more than 100mA,
2432                  * or 8mA for OTG ports */
2433                 if (udev->actconfig)
2434                         delta = udev->actconfig->desc.bMaxPower * 2;
2435                 else if (port1 != udev->bus->otg_port || hdev->parent)
2436                         delta = 100;
2437                 else
2438                         delta = 8;
2439                 if (delta > hub->mA_per_port)
2440                         dev_warn(&udev->dev, "%dmA is over %umA budget "
2441                                         "for port %d!\n",
2442                                         delta, hub->mA_per_port, port1);
2443                 remaining -= delta;
2444         }
2445         if (remaining < 0) {
2446                 dev_warn(hub->intfdev, "%dmA over power budget!\n",
2447                         - remaining);
2448                 remaining = 0;
2449         }
2450         return remaining;
2451 }
2452
2453 /* Handle physical or logical connection change events.
2454  * This routine is called when:
2455  *      a port connection-change occurs;
2456  *      a port enable-change occurs (often caused by EMI);
2457  *      usb_reset_device() encounters changed descriptors (as from
2458  *              a firmware download)
2459  * caller already locked the hub
2460  */
2461 static void hub_port_connect_change(struct usb_hub *hub, int port1,
2462                                         u16 portstatus, u16 portchange)
2463 {
2464         struct usb_device *hdev = hub->hdev;
2465         struct device *hub_dev = hub->intfdev;
2466         u16 wHubCharacteristics = le16_to_cpu(hub->descriptor->wHubCharacteristics);
2467         int status, i;
2468
2469         dev_dbg (hub_dev,
2470                 "port %d, status %04x, change %04x, %s\n",
2471                 port1, portstatus, portchange, portspeed (portstatus));
2472
2473         if (hub->has_indicators) {
2474                 set_port_led(hub, port1, HUB_LED_AUTO);
2475                 hub->indicator[port1-1] = INDICATOR_AUTO;
2476         }
2477
2478         /* Disconnect any existing devices under this port */
2479         if (hdev->children[port1-1])
2480                 usb_disconnect(&hdev->children[port1-1]);
2481         clear_bit(port1, hub->change_bits);
2482
2483 #ifdef  CONFIG_USB_OTG
2484         /* during HNP, don't repeat the debounce */
2485         if (hdev->bus->is_b_host)
2486                 portchange &= ~USB_PORT_STAT_C_CONNECTION;
2487 #endif
2488
2489         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2490                 status = hub_port_debounce(hub, port1);
2491                 if (status < 0) {
2492                         dev_err (hub_dev,
2493                                 "connect-debounce failed, port %d disabled\n",
2494                                 port1);
2495                         goto done;
2496                 }
2497                 portstatus = status;
2498         }
2499
2500         /* Return now if nothing is connected */
2501         if (!(portstatus & USB_PORT_STAT_CONNECTION)) {
2502
2503                 /* maybe switch power back on (e.g. root hub was reset) */
2504                 if ((wHubCharacteristics & HUB_CHAR_LPSM) < 2
2505                                 && !(portstatus & (1 << USB_PORT_FEAT_POWER)))
2506                         set_port_feature(hdev, port1, USB_PORT_FEAT_POWER);
2507
2508                 if (portstatus & USB_PORT_STAT_ENABLE)
2509                         goto done;
2510                 return;
2511         }
2512
2513 #ifdef  CONFIG_USB_SUSPEND
2514         /* If something is connected, but the port is suspended, wake it up. */
2515         if (portstatus & USB_PORT_STAT_SUSPEND) {
2516                 status = hub_port_resume(hub, port1, NULL);
2517                 if (status < 0) {
2518                         dev_dbg(hub_dev,
2519                                 "can't clear suspend on port %d; %d\n",
2520                                 port1, status);
2521                         goto done;
2522                 }
2523         }
2524 #endif
2525
2526         for (i = 0; i < SET_CONFIG_TRIES; i++) {
2527                 struct usb_device *udev;
2528
2529                 /* reallocate for each attempt, since references
2530                  * to the previous one can escape in various ways
2531                  */
2532                 udev = usb_alloc_dev(hdev, hdev->bus, port1);
2533                 if (!udev) {
2534                         dev_err (hub_dev,
2535                                 "couldn't allocate port %d usb_device\n",
2536                                 port1);
2537                         goto done;
2538                 }
2539
2540                 usb_set_device_state(udev, USB_STATE_POWERED);
2541                 udev->speed = USB_SPEED_UNKNOWN;
2542                 udev->bus_mA = hub->mA_per_port;
2543
2544                 /* set the address */
2545                 choose_address(udev);
2546                 if (udev->devnum <= 0) {
2547                         status = -ENOTCONN;     /* Don't retry */
2548                         goto loop;
2549                 }
2550
2551                 /* reset and get descriptor */
2552                 status = hub_port_init(hub, udev, port1, i);
2553                 if (status < 0)
2554                         goto loop;
2555
2556                 /* consecutive bus-powered hubs aren't reliable; they can
2557                  * violate the voltage drop budget.  if the new child has
2558                  * a "powered" LED, users should notice we didn't enable it
2559                  * (without reading syslog), even without per-port LEDs
2560                  * on the parent.
2561                  */
2562                 if (udev->descriptor.bDeviceClass == USB_CLASS_HUB
2563                                 && udev->bus_mA <= 100) {
2564                         u16     devstat;
2565
2566                         status = usb_get_status(udev, USB_RECIP_DEVICE, 0,
2567                                         &devstat);
2568                         if (status < 2) {
2569                                 dev_dbg(&udev->dev, "get status %d ?\n", status);
2570                                 goto loop_disable;
2571                         }
2572                         le16_to_cpus(&devstat);
2573                         if ((devstat & (1 << USB_DEVICE_SELF_POWERED)) == 0) {
2574                                 dev_err(&udev->dev,
2575                                         "can't connect bus-powered hub "
2576                                         "to this port\n");
2577                                 if (hub->has_indicators) {
2578                                         hub->indicator[port1-1] =
2579                                                 INDICATOR_AMBER_BLINK;
2580                                         schedule_work (&hub->leds);
2581                                 }
2582                                 status = -ENOTCONN;     /* Don't retry */
2583                                 goto loop_disable;
2584                         }
2585                 }
2586
2587                 /* check for devices running slower than they could */
2588                 if (le16_to_cpu(udev->descriptor.bcdUSB) >= 0x0200
2589                                 && udev->speed == USB_SPEED_FULL
2590                                 && highspeed_hubs != 0)
2591                         check_highspeed (hub, udev, port1);
2592
2593                 /* Store the parent's children[] pointer.  At this point
2594                  * udev becomes globally accessible, although presumably
2595                  * no one will look at it until hdev is unlocked.
2596                  */
2597                 status = 0;
2598
2599                 /* We mustn't add new devices if the parent hub has
2600                  * been disconnected; we would race with the
2601                  * recursively_mark_NOTATTACHED() routine.
2602                  */
2603                 spin_lock_irq(&device_state_lock);
2604                 if (hdev->state == USB_STATE_NOTATTACHED)
2605                         status = -ENOTCONN;
2606                 else
2607                         hdev->children[port1-1] = udev;
2608                 spin_unlock_irq(&device_state_lock);
2609
2610                 /* Run it through the hoops (find a driver, etc) */
2611                 if (!status) {
2612                         status = usb_new_device(udev);
2613                         if (status) {
2614                                 spin_lock_irq(&device_state_lock);
2615                                 hdev->children[port1-1] = NULL;
2616                                 spin_unlock_irq(&device_state_lock);
2617                         }
2618                 }
2619
2620                 if (status)
2621                         goto loop_disable;
2622
2623                 status = hub_power_remaining(hub);
2624                 if (status)
2625                         dev_dbg(hub_dev, "%dmA power budget left\n", status);
2626
2627                 return;
2628
2629 loop_disable:
2630                 hub_port_disable(hub, port1, 1);
2631 loop:
2632                 ep0_reinit(udev);
2633                 release_address(udev);
2634                 usb_put_dev(udev);
2635                 if (status == -ENOTCONN)
2636                         break;
2637         }
2638
2639 done:
2640         hub_port_disable(hub, port1, 1);
2641 }
2642
2643 static void hub_events(void)
2644 {
2645         struct list_head *tmp;
2646         struct usb_device *hdev;
2647         struct usb_interface *intf;
2648         struct usb_hub *hub;
2649         struct device *hub_dev;
2650         u16 hubstatus;
2651         u16 hubchange;
2652         u16 portstatus;
2653         u16 portchange;
2654         int i, ret;
2655         int connect_change;
2656
2657         /*
2658          *  We restart the list every time to avoid a deadlock with
2659          * deleting hubs downstream from this one. This should be
2660          * safe since we delete the hub from the event list.
2661          * Not the most efficient, but avoids deadlocks.
2662          */
2663         while (1) {
2664
2665                 /* Grab the first entry at the beginning of the list */
2666                 spin_lock_irq(&hub_event_lock);
2667                 if (list_empty(&hub_event_list)) {
2668                         spin_unlock_irq(&hub_event_lock);
2669                         break;
2670                 }
2671
2672                 tmp = hub_event_list.next;
2673                 list_del_init(tmp);
2674
2675                 hub = list_entry(tmp, struct usb_hub, event_list);
2676                 hdev = hub->hdev;
2677                 intf = to_usb_interface(hub->intfdev);
2678                 hub_dev = &intf->dev;
2679
2680                 i = hub->resume_root_hub;
2681
2682                 dev_dbg(hub_dev, "state %d ports %d chg %04x evt %04x%s\n",
2683                                 hdev->state, hub->descriptor
2684                                         ? hub->descriptor->bNbrPorts
2685                                         : 0,
2686                                 /* NOTE: expects max 15 ports... */
2687                                 (u16) hub->change_bits[0],
2688                                 (u16) hub->event_bits[0],
2689                                 i ? ", resume root" : "");
2690
2691                 usb_get_intf(intf);
2692                 spin_unlock_irq(&hub_event_lock);
2693
2694                 /* Is this is a root hub wanting to reactivate the downstream
2695                  * ports?  If so, be sure the interface resumes even if its
2696                  * stub "device" node was never suspended.
2697                  */
2698                 if (i) {
2699                         dpm_runtime_resume(&hdev->dev);
2700                         dpm_runtime_resume(&intf->dev);
2701                         usb_put_intf(intf);
2702                         continue;
2703                 }
2704
2705                 /* Lock the device, then check to see if we were
2706                  * disconnected while waiting for the lock to succeed. */
2707                 if (locktree(hdev) < 0) {
2708                         usb_put_intf(intf);
2709                         continue;
2710                 }
2711                 if (hub != usb_get_intfdata(intf))
2712                         goto loop;
2713
2714                 /* If the hub has died, clean up after it */
2715                 if (hdev->state == USB_STATE_NOTATTACHED) {
2716                         hub_pre_reset(hub, 0);
2717                         goto loop;
2718                 }
2719
2720                 /* If this is an inactive or suspended hub, do nothing */
2721                 if (hub->quiescing)
2722                         goto loop;
2723
2724                 if (hub->error) {
2725                         dev_dbg (hub_dev, "resetting for error %d\n",
2726                                 hub->error);
2727
2728                         ret = usb_reset_device(hdev);
2729                         if (ret) {
2730                                 dev_dbg (hub_dev,
2731                                         "error resetting hub: %d\n", ret);
2732                                 goto loop;
2733                         }
2734
2735                         hub->nerrors = 0;
2736                         hub->error = 0;
2737                 }
2738
2739                 /* deal with port status changes */
2740                 for (i = 1; i <= hub->descriptor->bNbrPorts; i++) {
2741                         if (test_bit(i, hub->busy_bits))
2742                                 continue;
2743                         connect_change = test_bit(i, hub->change_bits);
2744                         if (!test_and_clear_bit(i, hub->event_bits) &&
2745                                         !connect_change && !hub->activating)
2746                                 continue;
2747
2748                         ret = hub_port_status(hub, i,
2749                                         &portstatus, &portchange);
2750                         if (ret < 0)
2751                                 continue;
2752
2753                         if (hub->activating && !hdev->children[i-1] &&
2754                                         (portstatus &
2755                                                 USB_PORT_STAT_CONNECTION))
2756                                 connect_change = 1;
2757
2758                         if (portchange & USB_PORT_STAT_C_CONNECTION) {
2759                                 clear_port_feature(hdev, i,
2760                                         USB_PORT_FEAT_C_CONNECTION);
2761                                 connect_change = 1;
2762                         }
2763
2764                         if (portchange & USB_PORT_STAT_C_ENABLE) {
2765                                 if (!connect_change)
2766                                         dev_dbg (hub_dev,
2767                                                 "port %d enable change, "
2768                                                 "status %08x\n",
2769                                                 i, portstatus);
2770                                 clear_port_feature(hdev, i,
2771                                         USB_PORT_FEAT_C_ENABLE);
2772
2773                                 /*
2774                                  * EM interference sometimes causes badly
2775                                  * shielded USB devices to be shutdown by
2776                                  * the hub, this hack enables them again.
2777                                  * Works at least with mouse driver.
2778                                  */
2779                                 if (!(portstatus & USB_PORT_STAT_ENABLE)
2780                                     && !connect_change
2781                                     && hdev->children[i-1]) {
2782                                         dev_err (hub_dev,
2783                                             "port %i "
2784                                             "disabled by hub (EMI?), "
2785                                             "re-enabling...\n",
2786                                                 i);
2787                                         connect_change = 1;
2788                                 }
2789                         }
2790
2791                         if (portchange & USB_PORT_STAT_C_SUSPEND) {
2792                                 clear_port_feature(hdev, i,
2793                                         USB_PORT_FEAT_C_SUSPEND);
2794                                 if (hdev->children[i-1]) {
2795                                         ret = remote_wakeup(hdev->
2796                                                         children[i-1]);
2797                                         if (ret < 0)
2798                                                 connect_change = 1;
2799                                 } else {
2800                                         ret = -ENODEV;
2801                                         hub_port_disable(hub, i, 1);
2802                                 }
2803                                 dev_dbg (hub_dev,
2804                                         "resume on port %d, status %d\n",
2805                                         i, ret);
2806                         }
2807
2808                         if (portchange & USB_PORT_STAT_C_OVERCURRENT) {
2809                                 dev_err (hub_dev,
2810                                         "over-current change on port %d\n",
2811                                         i);
2812                                 clear_port_feature(hdev, i,
2813                                         USB_PORT_FEAT_C_OVER_CURRENT);
2814                                 hub_power_on(hub);
2815                         }
2816
2817                         if (portchange & USB_PORT_STAT_C_RESET) {
2818                                 dev_dbg (hub_dev,
2819                                         "reset change on port %d\n",
2820                                         i);
2821                                 clear_port_feature(hdev, i,
2822                                         USB_PORT_FEAT_C_RESET);
2823                         }
2824
2825                         if (connect_change)
2826                                 hub_port_connect_change(hub, i,
2827                                                 portstatus, portchange);
2828                 } /* end for i */
2829
2830                 /* deal with hub status changes */
2831                 if (test_and_clear_bit(0, hub->event_bits) == 0)
2832                         ;       /* do nothing */
2833                 else if (hub_hub_status(hub, &hubstatus, &hubchange) < 0)
2834                         dev_err (hub_dev, "get_hub_status failed\n");
2835                 else {
2836                         if (hubchange & HUB_CHANGE_LOCAL_POWER) {
2837                                 dev_dbg (hub_dev, "power change\n");
2838                                 clear_hub_feature(hdev, C_HUB_LOCAL_POWER);
2839                                 if (hubstatus & HUB_STATUS_LOCAL_POWER)
2840                                         /* FIXME: Is this always true? */
2841                                         hub->limited_power = 0;
2842                                 else
2843                                         hub->limited_power = 1;
2844                         }
2845                         if (hubchange & HUB_CHANGE_OVERCURRENT) {
2846                                 dev_dbg (hub_dev, "overcurrent change\n");
2847                                 msleep(500);    /* Cool down */
2848                                 clear_hub_feature(hdev, C_HUB_OVER_CURRENT);
2849                                 hub_power_on(hub);
2850                         }
2851                 }
2852
2853                 hub->activating = 0;
2854
2855                 /* If this is a root hub, tell the HCD it's okay to
2856                  * re-enable port-change interrupts now. */
2857                 if (!hdev->parent)
2858                         usb_enable_root_hub_irq(hdev->bus);
2859
2860 loop:
2861                 usb_unlock_device(hdev);
2862                 usb_put_intf(intf);
2863
2864         } /* end while (1) */
2865 }
2866
2867 static int hub_thread(void *__unused)
2868 {
2869         do {
2870                 hub_events();
2871                 wait_event_interruptible(khubd_wait,
2872                                 !list_empty(&hub_event_list) ||
2873                                 kthread_should_stop());
2874                 try_to_freeze();
2875         } while (!kthread_should_stop() || !list_empty(&hub_event_list));
2876
2877         pr_debug("%s: khubd exiting\n", usbcore_name);
2878         return 0;
2879 }
2880
2881 static struct usb_device_id hub_id_table [] = {
2882     { .match_flags = USB_DEVICE_ID_MATCH_DEV_CLASS,
2883       .bDeviceClass = USB_CLASS_HUB},
2884     { .match_flags = USB_DEVICE_ID_MATCH_INT_CLASS,
2885       .bInterfaceClass = USB_CLASS_HUB},
2886     { }                                         /* Terminating entry */
2887 };
2888
2889 MODULE_DEVICE_TABLE (usb, hub_id_table);
2890
2891 static struct usb_driver hub_driver = {
2892         .name =         "hub",
2893         .probe =        hub_probe,
2894         .disconnect =   hub_disconnect,
2895         .suspend =      hub_suspend,
2896         .resume =       hub_resume,
2897         .ioctl =        hub_ioctl,
2898         .id_table =     hub_id_table,
2899 };
2900
2901 int usb_hub_init(void)
2902 {
2903         if (usb_register(&hub_driver) < 0) {
2904                 printk(KERN_ERR "%s: can't register hub driver\n",
2905                         usbcore_name);
2906                 return -1;
2907         }
2908
2909         khubd_task = kthread_run(hub_thread, NULL, "khubd");
2910         if (!IS_ERR(khubd_task))
2911                 return 0;
2912
2913         /* Fall through if kernel_thread failed */
2914         usb_deregister(&hub_driver);
2915         printk(KERN_ERR "%s: can't start khubd\n", usbcore_name);
2916
2917         return -1;
2918 }
2919
2920 void usb_hub_cleanup(void)
2921 {
2922         kthread_stop(khubd_task);
2923
2924         /*
2925          * Hub resources are freed for us by usb_deregister. It calls
2926          * usb_driver_purge on every device which in turn calls that
2927          * devices disconnect function if it is using this driver.
2928          * The hub_disconnect function takes care of releasing the
2929          * individual hub resources. -greg
2930          */
2931         usb_deregister(&hub_driver);
2932 } /* usb_hub_cleanup() */
2933
2934 static int config_descriptors_changed(struct usb_device *udev)
2935 {
2936         unsigned                        index;
2937         unsigned                        len = 0;
2938         struct usb_config_descriptor    *buf;
2939
2940         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2941                 if (len < le16_to_cpu(udev->config[index].desc.wTotalLength))
2942                         len = le16_to_cpu(udev->config[index].desc.wTotalLength);
2943         }
2944         buf = kmalloc (len, SLAB_KERNEL);
2945         if (buf == NULL) {
2946                 dev_err(&udev->dev, "no mem to re-read configs after reset\n");
2947                 /* assume the worst */
2948                 return 1;
2949         }
2950         for (index = 0; index < udev->descriptor.bNumConfigurations; index++) {
2951                 int length;
2952                 int old_length = le16_to_cpu(udev->config[index].desc.wTotalLength);
2953
2954                 length = usb_get_descriptor(udev, USB_DT_CONFIG, index, buf,
2955                                 old_length);
2956                 if (length < old_length) {
2957                         dev_dbg(&udev->dev, "config index %d, error %d\n",
2958                                         index, length);
2959                         break;
2960                 }
2961                 if (memcmp (buf, udev->rawdescriptors[index], old_length)
2962                                 != 0) {
2963                         dev_dbg(&udev->dev, "config index %d changed (#%d)\n",
2964                                 index, buf->bConfigurationValue);
2965                         break;
2966                 }
2967         }
2968         kfree(buf);
2969         return index != udev->descriptor.bNumConfigurations;
2970 }
2971
2972 /**
2973  * usb_reset_device - perform a USB port reset to reinitialize a device
2974  * @udev: device to reset (not in SUSPENDED or NOTATTACHED state)
2975  *
2976  * WARNING - don't reset any device unless drivers for all of its
2977  * interfaces are expecting that reset!  Maybe some driver->reset()
2978  * method should eventually help ensure sufficient cooperation.
2979  *
2980  * Do a port reset, reassign the device's address, and establish its
2981  * former operating configuration.  If the reset fails, or the device's
2982  * descriptors change from their values before the reset, or the original
2983  * configuration and altsettings cannot be restored, a flag will be set
2984  * telling khubd to pretend the device has been disconnected and then
2985  * re-connected.  All drivers will be unbound, and the device will be
2986  * re-enumerated and probed all over again.
2987  *
2988  * Returns 0 if the reset succeeded, -ENODEV if the device has been
2989  * flagged for logical disconnection, or some other negative error code
2990  * if the reset wasn't even attempted.
2991  *
2992  * The caller must own the device lock.  For example, it's safe to use
2993  * this from a driver probe() routine after downloading new firmware.
2994  * For calls that might not occur during probe(), drivers should lock
2995  * the device using usb_lock_device_for_reset().
2996  */
2997 int usb_reset_device(struct usb_device *udev)
2998 {
2999         struct usb_device               *parent_hdev = udev->parent;
3000         struct usb_hub                  *parent_hub;
3001         struct usb_device_descriptor    descriptor = udev->descriptor;
3002         struct usb_hub                  *hub = NULL;
3003         int                             i, ret = 0;
3004         int                             port1 = udev->portnum;
3005
3006         if (udev->state == USB_STATE_NOTATTACHED ||
3007                         udev->state == USB_STATE_SUSPENDED) {
3008                 dev_dbg(&udev->dev, "device reset not allowed in state %d\n",
3009                                 udev->state);
3010                 return -EINVAL;
3011         }
3012
3013         if (!parent_hdev) {
3014                 /* this requires hcd-specific logic; see OHCI hc_restart() */
3015                 dev_dbg(&udev->dev, "%s for root hub!\n", __FUNCTION__);
3016                 return -EISDIR;
3017         }
3018         parent_hub = hdev_to_hub(parent_hdev);
3019
3020         /* If we're resetting an active hub, take some special actions */
3021         if (udev->actconfig &&
3022                         udev->actconfig->interface[0]->dev.driver ==
3023                                 &hub_driver.driver &&
3024                         (hub = hdev_to_hub(udev)) != NULL) {
3025                 hub_pre_reset(hub, 0);
3026         }
3027
3028         set_bit(port1, parent_hub->busy_bits);
3029         for (i = 0; i < SET_CONFIG_TRIES; ++i) {
3030
3031                 /* ep0 maxpacket size may change; let the HCD know about it.
3032                  * Other endpoints will be handled by re-enumeration. */
3033                 ep0_reinit(udev);
3034                 ret = hub_port_init(parent_hub, udev, port1, i);
3035                 if (ret >= 0)
3036                         break;
3037         }
3038         clear_bit(port1, parent_hub->busy_bits);
3039         if (ret < 0)
3040                 goto re_enumerate;
3041
3042         /* Device might have changed firmware (DFU or similar) */
3043         if (memcmp(&udev->descriptor, &descriptor, sizeof descriptor)
3044                         || config_descriptors_changed (udev)) {
3045                 dev_info(&udev->dev, "device firmware changed\n");
3046                 udev->descriptor = descriptor;  /* for disconnect() calls */
3047                 goto re_enumerate;
3048         }
3049
3050         if (!udev->actconfig)
3051                 goto done;
3052
3053         ret = usb_control_msg(udev, usb_sndctrlpipe(udev, 0),
3054                         USB_REQ_SET_CONFIGURATION, 0,
3055                         udev->actconfig->desc.bConfigurationValue, 0,
3056                         NULL, 0, USB_CTRL_SET_TIMEOUT);
3057         if (ret < 0) {
3058                 dev_err(&udev->dev,
3059                         "can't restore configuration #%d (error=%d)\n",
3060                         udev->actconfig->desc.bConfigurationValue, ret);
3061                 goto re_enumerate;
3062         }
3063         usb_set_device_state(udev, USB_STATE_CONFIGURED);
3064
3065         for (i = 0; i < udev->actconfig->desc.bNumInterfaces; i++) {
3066                 struct usb_interface *intf = udev->actconfig->interface[i];
3067                 struct usb_interface_descriptor *desc;
3068
3069                 /* set_interface resets host side toggle even
3070                  * for altsetting zero.  the interface may have no driver.
3071                  */
3072                 desc = &intf->cur_altsetting->desc;
3073                 ret = usb_set_interface(udev, desc->bInterfaceNumber,
3074                         desc->bAlternateSetting);
3075                 if (ret < 0) {
3076                         dev_err(&udev->dev, "failed to restore interface %d "
3077                                 "altsetting %d (error=%d)\n",
3078                                 desc->bInterfaceNumber,
3079                                 desc->bAlternateSetting,
3080                                 ret);
3081                         goto re_enumerate;
3082                 }
3083         }
3084
3085 done:
3086         if (hub)
3087                 hub_post_reset(hub);
3088         return 0;
3089
3090 re_enumerate:
3091         hub_port_logical_disconnect(parent_hub, port1);
3092         return -ENODEV;
3093 }